Bakemonogatari has Psycho Lesbian Suruga who is dangerously in love with Hitagi. So much so that she starts stalking Koyomi after he hooks up with Hitagi and tries to beat him to death twice. And then her later actions towards him are sort of reverse Ho Yay (Straight Yay?)
Tsubasa's descriptions of Hitagi during "Suruga Monkey", where she seems to trail off into deep thought as she says how beautiful Hitagi is.
There's a scene in episode 8 where Oshino walks up to Koyomi and leans in so close to him that their faces are a mere few inches apart.
Nekomonogatari (White) makes self-aware pokes at the trope, as Senjougahara starts making suggestive comments to Hanekawa out of nowhere while denying that they are in any way suggestive. They end up showering together (complete with Skinship Grope) and sharing a futon for the night.