I'm looking for a manga

Hello, I'm looking for a manga where the seme is a spider demon and the uke is a monk. I remembered that the seme is petite a d the uke is kind of buff. The uke is human (I think) and every time he sleeps it lasts for years and it became longer as time passby. The spider demon sheds its skin and when the monk wakes up he saw the spider demon mature.

I hope someone knows the title( ≧Д≦). I don't know why these days I like to reread again mangas I read and read again in the past.....