In what circumstances does or would your character drink alcohol? (e.g. "with a meal, for fun, when depressed, at any excuse, NEVER EVER") Buffy does not believe in drinking anymore. The magical beer that turned her into Cave Buffy apparently left a bad taste in her mouth forever. Or at least until Season 6 crashes depression on her head, one or the other!
How much would they normally consume? Do they get drunk every once in a while, or live and breathe alcohol, or make sure to stay under the legal limit? Every time Buffy's ever gotten drunk in canon, she's gotten completely hammered. But two of those times were magic, and two of them involved trying to dull the pain, so I'd imagine that in a lighter context Buffy would prefer a gentle buzz for relaxation after a hard night's slay.
How much alcohol tolerance do they have? Does even a sniff of alcohol knock them over, or can they guzzle alcohol without feeling impaired? Slayer metabolism. Without it, Buffy would be the lightest lightweight to ever lightweight. Even with it, she can and does get very drunk in relatively short periods of time.
What kind of drunk is your character? How would they act if they were drunk? Buffy is sort of a "silly" drunk. She giggles and wobbles and pouts. She tells Xander that he is totally one of the girls. She tips over a box of kittens and tells them to be free!
Who would they go drinking with if they had to choose drinking buddies? Hmmmm. Of the people here, Spike and Zero are both prime contenders. Buffy is still somewhat wary of Faith, and so less likely to go drinking with her; and it frankly weirds her out a little to imagine Willow drinking.
What's their alcohol preferences? Beer, wine, mixed drinks with fancy names? Buffy gives this question something of a blank look, then maybe makes up a sophisticated-sounding name for her favorite drink off the top of her head. She's not big on the subtle differences between different types of alcohol, but she's always had beer in canon.
Green alcohol y/n? SURE WHY NOT. If Buffy's having a binge, all beer colors are welcome. If she's out on the town with friends drinking more casually, then green beer seems extra fun and festive.
Your character is completely drunk. (If your character would never get drunk, they were tied to a chair and alcohol was funnelled down their throat.) (If your character is physically incapable of getting drunk, it is magical alcohol that affects them anyway.) (Then they woke up with no memory of how they got smashed.) The point is that your character is completely drunk. Who do they drunk-dial, and what do they say? Here? Aidou is a good candidate. Buffy would call him, full of apologies for that first day, and also accusations, because hey, you can't espec-- esspeect-- you can't just build up this perfect picture in your head of someone before meeting them, and even if you do, it's YOUR fault if that picture is wrong! Not her fault! Nope! Not even a little! And why was Spike talking to you so much about her anyway, Spike is so weird..... etc.