Not so much mystery but still a decent psychological one:
https://mangadex.org/title/46103/juujika-no-rokunin
Then a really good mystery one:
https://mangadex.org/title/42211/disease
I love this. It reminds me a lot of guns akimbo,(which is the movie that spawned the meme of Daniel Radcliffe in a bathrobe/slippers holding 2 guns.) if you like this go watch the movie. Very similar premise, fucking hilarious.
I’m glad that this manga does the LN justice. Although it is cringey, you get used to it after awhile and the plots pretty good. Although I might be a bit biased seeing as this was the first light novel I read
In the light novels he is a lot closer to the others who were summoned with him. The other guy who was summoned in the light novels was a closet otaku and they instantly bonded over a large amount of references to modern culture.