NOVEL NEXT Chapter 40: 40reincarnated as issei(dxd) with an entire body made out of parasyte cells(parasyte)
Mc reincarnates as issei from birth, has no knowlage of dxd world, mc's cheat is that his entire body is made out of parasyte cells without the racial drawbacks(lack of emotions, canibalistic instinct, inability to get more cells then what you started with(migi got crippled in canon when he lost some microscopic chunks of himself, it was realy not a lot of mass that he lost at all, but it was still very detrimental to him)). Mc will porsue a carrer in biology, as he can replicate animals' organs with enought study(eagle eyes, fish gills, stuff like that), he can also replicate SOME tech(i wanted mc to make the intro song of the parasyte anime "let me hear", and it would be a waste to get into an entire band for just 1 song, so mc will just change his body into a speaker and sing to his computer's microphone with all the instruments) but mc will NOT be able to interface with a computer or anything like that
Mc will discover the supernatural world same as the original issei: with raynare trying to kill him, but diferently from canon, raynare will skip the date and just ambush mc on his way home, raynare will just aproach mc in her yumma disquise and ask "mister, will you die for me?" mc will play along beeing confused and then scared when she reveals her wings and let her talk for a bit to get more information, but when she trows her light spear, mc unfurls his head parasyte style and behead her wile dodging the spear, mc then proceeds to diesect raynare's body to study it, wings especionaly, mc noticed he was in a world with magic when raynare made the light spear and got quite exited at the prospect of beeing able to learn magic one day, that desire to learn magic ends up summoning rias
Mc will become rias' pawn and become a bit of a spellcaster, as the parasyte body alone won't be able to carry mc through the verse, i am unsure if mc will have a sacred gear or not, but i am leaning on "yes" and a boosted gear subspecies. Mc will probably make a dimensional storage spell to store his cells, that way he can keep making more and not worry about getting abnormaly tall or heavy, a spell to keep him light so he can up his own density and therefore be stronger without, again, getting abnormaly heavy and raising suspicion on the humans
Mc probably won't say he is a reincarnator, but he will probably tell rias that he is an alien(she'd kinda find him next to a beheaded and partialy diesected body of a fallen angel with no blade in sight, so mc will have some explaining to do)