Hello, please help me, because this has been driving me insane.
The manga I'm looking for has a very nice art (kind of reminds me of donten ni warau) and it;s about this one guy who has a few familiars and although he is solving things in our world he actually lives in this monster/demon world that you travel to through water (but him and his familiar (I want to say Tenko) break through illegally all the time).

He has this one familiar that looks like a little girl and bites a lot, and one who is super powerful and a very important person and kind of looks like a tiger and then after one mission he also gets this boy who is actually a lightening beast. Also the main familiar seems to be mysteriously strong and have some sort of double personality thing going.

the manga is mainly with the main character grown up but there were a few chapters in which he's a kid (they describe how he gets his first familiar in that).

that's all I remember, I hope it's enough!

6 no trigger??