It doesn´t need to be fully focusing on the lesbian side, but it should at least be one of the themes of the game. Lesbian monster sex, and futa on female is good as well. I´ll list most of the games like this that I´ve already played:
Trinity dungeon - Here monster sex is the main focus, but still there is a good amount of lesbian scenes.
Horny bunny Hana - This has only a small amount of lesbian sex, but still the main relationship of the game is lesbian so it makes up for it.
Overgrown genesis - this game had some of it as well.
Demon master chris - another game with monster sex and lesbian conent with female MC.
Lighting Warrior Raidy - game fully focusing on lesbian bdsm.
Trinity dungeon - Here monster sex is the main focus, but still there is a good amount of lesbian scenes.
Horny bunny Hana - This has only a small amount of lesbian sex, but still the main relationship of the game is lesbian so it makes up for it.
Overgrown genesis - this game had some of it as well.
Demon master chris - another game with monster sex and lesbian conent with female MC.
Lighting Warrior Raidy - game fully focusing on lesbian bdsm.