This is a very fun metroidvania-style game. The enemies are all girls that attack by having hearts come out of their faces, panties, etc. Honestly though I don't find it very sexy but the game is so fun it's worth playing anyway. Game is brutal, definitely recommend playing on easy. Very easy everything just instadies and that's too easy though.
It's easy to get stuck and not know how to progress, but the main trick is about beating bosses to get new weapons. You can destroy the colored walls if you use a weapon of the appropriate color. E.g. the fire weapon to destroy the blue walls and the blue weapon to destroy the orange walls. You may also need to find something with cold resistance to get through the cold area, but I found the hot area is possible without heat resistance it's just painful. Anyway hope that helps you not get stuck too long in this game.
You can find the game here: https://www.onlyhgames.com/mega-sis-one-shotamon-girl-exploration-action-rpg/