The Lover is twenty, and the time of the year is May. On the Lover's first approach to the Garden, he finds that the world of courtly life excludes (obvious) vices, poverty, age, sadness, and religious prudishness. The keeper of the gate is Idleness; courtly life is for those who have leisure, and, what is more, idle leisure (as opposed to leisure for study or prayer).
Within the Garden, the Lover comes upon the Fountain of Narcissus (the perilous mirror), where he falls in love. The linking of falling in love with Narcissus is interesting. I think C. S. Lewis somewhere associates the fountain with the Lady's eyes; the eyes mirror back the image the mind projects on them, and we fall in love with reflections of our own fantasies and dreams. The God of Love strikes the Lover with five arrows: Beauty, Simplicity, Courtesy, Company, and Fair-seeming. These arrows give the Lover the Pains of Love: insomnia, loss of appetite, erotic dreams, etc. The God locks the Lover's heart (the seat of his understanding) and gives him commandments - the obvious things, like 'Have a good sense of fashion', 'Look good on horseback', 'Learn how to play a musical instrument' - all the things that help make the women pay attention to you.
The Lover develops a desire for the Lady's Rose (and the Rose is, well, you know what the Rose is). The bulk of the story is the allegorical depiction of how various aspects of the Lady's life aid or hinder the Lover's quest for the Rose. On the Lover's side are Bialacoil (fair-welcome), the son of Courtesy; Franchise; and Pity. Fair-welcome: the Lady wishes to be open-minded, benevolent, 'nice'. Bialacoil is the part of the Lady that is already entirely on the Lover's side, and will be the Lover's primary helper; she wants to be nice to him, partly because that's just the sort of good girl she is, and partly because she does genuinely like him (in a general sense of liking). Franchise is the Lady's innocent security: she has led a protected life, born to no great hardship, and she has a certain naivete about the world: she is secure and freeborn, and has not been taught life's harder lessons. Pity is the Lady's desire not to let the Lover suffer; roughly, her desire to ease the pain of his love for her and not to hurt his feelings.
Against the Lover, however, is a formidable set of foes. These are Fear, Shame, and Daungier (Danger). Fear and Shame are obvious opponents to the Lover's cause; but they turn out not to be nearly so formidable as they seem. When Venus (the sheer animal force of sexual attraction) descends, Fear and Shame, so apparently fierce, become utterly helpless. Danger is another story, however, and in fact Guillaume de Lorris's actual poem, as we have it (it is incomplete), is the story of the Lover's failure to neutralize Danger completely. Daungier, Lewis suggests, is the Lady's pride, her ultimately and most powerful protection from people who would use her or treat her poorly: it is the terror of lovers and the most aggressive and brutal (to lovers!) defense of the woman's heart. Fear and Shame may become helpless in the face of Venus, but Daungier has to be lulled to sleep before any progress can be made.
The Lover, obviously, wants to pluck the Rose; but it is well-guarded. The Lover is actually doing fairly well at the beginning. Bialacoil goes so far as to offer the Lover a leaf near the Rose. Apparently the Lady feels a bit flirtatious; perhaps she is giving him a little love-token. But the Lover spoils this by asking outright for the Rose; Daungier suddenly wakes from sleep, forces the Lover to retreat, and terrorizes Bialacoil.
Poor Lover! Now things are worse, and he is forced to take time to reflect. Reason descends in glory and gives him a lecture full of good advice. The Lover is not too happy with what she tells him, though, because she is effectively telling him to leave the service of Love. So he tries to find a second opinion that will be more in keeping with what he wants. This he finds in Friend, who tells him exactly what he wants to hear, as friends no doubt often do.
Meanwhile, Daungier has subsided; the brute is no longer on a rampage. It has been awakened, however, and stays awake; it keeps a sharp eye on the Rose, watching the Lover with suspicion. Bialacoil is in exile; he has, as far as Daungier is concerned, virtually caused the whole incident. If you go around giving fair welcome to people who want the Rose, what else are you going to get? But the Lady is a courteous woman, not the sort to hold a grudge. Franchise and Pity set to work convincing Daungier to let Bialacoil return. Part of the Lady really does feel sorry for the Lover, who maybe didn't really mean anything by it, and, in any case, what harm can he really do? Just because the Lover was impudent and indiscreet is no reason for her to be mean. She can still be friends; she can still be nice to him. And Daungier relents. Bialacoil returns and soon we are almost right back to where we were: Bialacoil is having a grand old time with the Lover. The Lover, more cautious now, asks to kiss the Rose - not to pluck it, just to kiss it. If she doesn't want to go all the way, he insists, he won't force the matter; but he would like a little something. Bialacoil, however, still is afraid of Daungier, and resists this idea. Resists it, that is, until Venus descends again and touches him with the torch. Handy goddess, that Venus. Bialacoil relents.
So the Lover kisses the Rose, and, alas, everything breaks into confusion. Malebouche (negative rumors and gossip) summons Jealousy (presumably of the Lady's husband: you didn't think she was unattached, did you? This is courtly love we're talking about - adultery is the order of the day). Bialacoil is thrown into prison, guarded by Fear, Shame, Daungier, and Malebouche. Fair welcome will not give the Lover access again.
And the poem ends, unfinished, here. Things aren't looking too good for the Lover's cause; his primary ally, and the real source of his success, is Bialacoil, who is locked up and guarded by an old woman: a chaperone. Things aren't entirely hopeless; Shame has difficulty believing that it is ever entirely wrong to extend fair welcome. But the Lady's nature, combined with social convention and the Lover's blunders, has led to the Lover's being blocked, and whatever hope there might be is very, very slight. The Lover has effectively checkmated himself. Jean de Meun, of course, wrote a more optimistic continuation; but that's another poem entirely.
It is interesting comparing this seduction in the Garden with another temptation in a garden, that of Eve by the cunning serpent. The serpent counters God's authoritative command (do not eat of the tree, or, dying, you shall die) by suggesting that God knows very well that if she eats of the tree she will not die but become like God. And then, the text says,
So when the woman saw that the tree was good for food, and that it was a delight to the eyes, and that the tree was to be desired to make one wise, she took of its fruit and ate, and she also gave some to her husband who was with her, and he ate.
The tree was good for food; delightful to the eyes; desirable for gaining insight. In other words, healthy, attractive, and a satisfaction to curiosity. (Is it just me, by the way, or is it a little funny how easily the husband falls here? It takes some effort for the serpent to bring the woman to that point; the woman just has to give the man the fruit and he chomps it down.)
What seduction in particular does, and temptation more generally, is to construct a sort of fantasy reality, one built out of apparent good (it seems so natural; it would be enjoyable; aren't you just a little bit curious?), thereby disassociating people from the truth - the moral truth, obviously, but also the natural truth. The Lover falls in love not with a Lady but with a reflection in the Fountain of Narcissus, that perilous mirror. The serpent doesn't merely try to cast aspersion on God's authority, he starts confusing Eve about what God actually said and meant in the first place. Seduction takes place in the realm of fantasy.
Commonly, the way this works is that the seducer or tempter develops a parallelism between what he wants and something completely innocent. It's good for food; it's delightful to the eyes; it's a way to learn something knew. Isn't it just a bit absurd to reject something that could be so healthy, so fun, so interesting? The serpent draws Eve away from the prohibition in order that she might just look at the tree. And the Lady's fair welcome and franchise - her benevolence and security - play right into this, by making it easier to confuse the distinction between fantasy (the innocent structure) and reality (the actual deed). It is this confusion that makes the difference between mere fantasy and actual seduction. So I would interpret these cases, anyway.
