u/Usernamelesses

It's been long enough since Buffy aired that entire social media platforms have come and gone (either literally or in popularity), so the answer would likely depend on what website/apps were popular during a given time.

For me, here is what comes to mind when I think of various character's social media vibe. Feel free to object or add your own:

Buffy - Facebook

• Activity: One of those people who never posts but occasionally will unexpectedly like someone's picture or status. Will occasionally click "attending" on school events she plans on attending. She only ever posted during her Homecoming Campaign, posting her poster and making statuses asking people to vote for her. These posts are immediately scrubbed from the internet upon her losing. Also is known to occasionally deactivate her account for varying spans of time.
• Profile Pic: Does not have a profile picture (it's just the default gray figure), but if you click on her albums, her previous profile pictures are all from her time at Hemery High (cheerleading pictures, May queen pictures, etc.) At one point she *MAYBE* puts the classic picture of her, Willow, and Xander laughing on the grass, but ultimately reverts back to gray figure. Realistically she will at some point have a picture of her with Riley as her profile picture.
• Friends: she is friends with basically every single Hemery High student in her grade + all the popular ones from other grades. She has never sent out a single friend request since leaving Hemery, but she instantly accepts friend requests from Sunndydale, resulting in an incoherent lineup of random facebook friends.

Xander - Twitter

• Posts random thoughts
• Posts every joke that he feels the Scoobies don't laugh at enough
• Posts every joke that the Scoobies do laugh at sufficiently
• Posts random phrases of wisdom
• Posts pics of his meals
• Very extreme range in the quality of his tweets.
• Obscurely gets a lot of followers but makes the decision to just pretend like it isn't happening.
• Screenshots of his tweets occasionally gets screenshotted and circulated as a meme on other websites.

Willow - 2010-2014 Tumblr and any era of Reddit

• Tumblr for seeking out witchy communities, and expressing herself via Tumblr blog aesthetic, love poems, Dougie Houser Fan Fiction, etc.
• Reddit for asking advice on both tech issues and spell issues.

Tara - Snapchat

• Primarily sends goofy little snaps to Willow, and occasionally Anya or Dawn
• Snaps things she finds aesthetically pleasing that she wants to share. Her goofy snaps are usually pictures of things that she sees during her day that are absurd, and she usually pairs it with a subtly witty caption.
• Understated and cryptic snapchat stories. Sometimes deleted before the 24 hour window ends.

Cordelia - Instagram

• Very curated to portray herself as lively and interesting but not messy or overly-online.
• Typical pictures include but are not limited to: cheerleading photos (both candids during a routine and team photos), family vacation photos, photos from school dances, and photos from that day at the wharf with Xander.
• MAYBE a mirror selfie with friends but only if her outfit is designer and stunning and the picture itself has very high aesthetic merit.
• In her very early days of Instagram use, would post pictures from the Bronze with those classic instagram filters, but would not be caught dead doing so after freshman year. She never deletes her old pics though because she's not ashamed of doing something that was innovative and trend-setting at the time.
• Does not view anyone's instagram stories except for guys she's dating. Never posts instagram stories unless it's for a prom/homecoming/May queen campaign.
• She only likes pictures based on merit, not friendship.

Dawn - MySpace and TikTok

• MySpace would have been a great place for Dawn to express herself and establish a sense of identity. She would love choosing songs for her page, etc.
• She has definitely made silly TikTok videos with friends at school.

Anya - LinkedIn and Facebook marketplace (and probably Zillow)

• You either see the vision or you don't.

Giles - YouTube

• Watches academic lectures and occasionally comments on them.
• Posted two acoustic guitar singing videos, but has probably since unlisted/privated them.

Riley - Pinterest

• 🤠