gay

You pick any of the sisters to fuck with first, then after finishing them you pick from the other two, then finally the last. You can do them in any order.
Youngest (Weeb) sister is the shortest. She only has one boy (maybe a second), but she's into gay stuff so she's willing to let you fuck her boyfriend, so you have to get creative to break them up.
Middle (Preppy) sister is longer. She's popular and rebounds quickly, so you have to ruin her reputation so guys stop dating her. She has the most guys in her section.
Oldest (Punky) sister is more complicated. She's in an open relationship with her boyfriend, so instead you need to break up their band. You go full Yoko Ono on him to pressure the band into falling apart. One of the things you can do to mess with the band is to sleep with at least one of the other members.
Maybe a second act where you have to deal with the harem you set up? Probably short, maybe more along the lines of a playable epilogue than a full act or something.