A yaoi manga about youkai, where the seme is a spider youkai - while the uke ( i think) claim to be a priest. They travel together, as the plot carries on the spider youkai who at first looks like a child grow into a teen when he seeds skin. I think the priest isnt a human too - but i forgot, since he looks like a human with no youkai traits
I literally read that last night lol its this one
http://www.mangago.me/read-manga/bouzu_to_kumo_buddhist_priest_spider/
As the MC said when the game's too easy it's no fun at all. The same with this manhwa.