Rimuru Tempest from "Tensei Slime Datta Ken" is bored in his world so he decides to reincarnate in another world. He ends up reincarnated as Hajime Nagumo's twin brother and ends up meddling in Arifureta's story: From Commonplace to World's Strongest.

(spoiler warnings for vol 12 of the lightnovel for Tensei slime) Danmachi x TSSDK A country loses its king, and another gains a final boss. Having died in the war with the eastern empire Rimuru finds himself in a completely unknown structure. with nowhere left to go and no particular goal in mind, he wanders upward. The gods of this new world sense something amiss with the dungeon. Some grow intrigued. Others fear the worst. Is the dungeon city Orario ready for the dungeon's final challenge? (I am not fully caught up on sword Oratorio at the moment so if any inconsistencies pop up that's why. also, vol 12 spoilers for that time I got reincarnated as a slime this version of rimuru is the version that chole talked about at the beginning of vol 12 who died in the war because he never evolved to a demonlord. on top of this, I'm going to take some creative liberties and change some events from danmachi to fit my story.) Disclaimer: I do not own That time I got reincarnated as a slime or Is it wrong to try to pick up girls in a dungeon. That time I got reincarnated as a slime is owned by Fuse and Eight-bit Studio. Is it wrong to try to pick up girls in a dungeon is owned by Fujino Ōmori and J.C. Staff. Please support the official release. Cover art is from Tensei shitara slime Datta ken lightnovel vol 5 illustrated by Mitz Vah