I played it for around an hour and must say you don't need good translation for this game. The story is absurd, as well as most sexual situations. MTL is passable, give you enough information to understand what you need to do and what is going on. But as I said, the story is not even trying to be serious, I would say this type of game, where you just hunt for scenes not thinking much about how they fit in with the main plot and the heroine's character. For example, from the start, you can enter the house of ugly and stinky bastard and take his rotten underpants. Why you ask? For no reason, you can just do it, and start to trigger scenes with him, for now reason. The same goes with slum town where demons live, you can go there, buy drugs and become addict so after that you can trigger sex scenes. It's not justified by anything, you just can do it. Also, you can trigger sex event as many times as you want (at least that was the case in the resort town) and the dialogues always will be the same.
Not my cup of tea, I prefer more with a more serious plot and where the actions of the characters are at least a somewhat justified (Detective girl of the steam city, the curse of kubel, etc.)
TL;DR MTL is fine, you don't have to really get into what's going on, because everything in this game is made just to trigger sex scenes. The game is purely for a quick fap. Combat is easy as well.