Kimoi can mean creepy too, and given Tomoko's appearance when Ucchi met her, I lean towards that interpretation. But you're right either way. Kimoi キモい is in katakana and it's short for kimochi warui 気持ち悪い (feeling bad) which means either gross or creepy. And when you're talking about a person, あの人なんだか気味悪くない? means aren't they creepy? And I bring this up because Tomoko isn't filthy or anything. Yes, Ucchi probably does think lesbian stuff is gross, but when she's talking about Tomoko, my suspicion is she's saying she's a "creepy girl" or "creepy stalker." Yes, we see Ucchi as the creepy stalker, but she sees Tomoko that way (or did, and now she can't understand why she misses it).