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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 basically 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 of the first series where Oshino walks up to Koyomi and leans in so close to him that their faces are a mere few inches apart.
When the Meddlesome Cat (a male apparition, in a girl's body) grabs Koyomi from behind, he licks his neck in a very sensual way. Though the Cat's tongue is also sharp enough to let out a jet of blood.
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.
In Hanamonogatari, Numachi Rouka explicitly states that she is also a lesbian and asks Kanbaru if she wants to kiss, climbing over her and kissing her cheek instead. Later, something similar happens where Numachi ends up under Kanbaru after trying to defend against a slam dunk. They stay like that for about a minute while laughing together. Kanbaru thinks to herself "Oh wow. She's really cute. I probably should have kissed her."