Cant remember title

#1
It is about a fuy that gets transported to another world and ends up inside a dragon and kills it causing him to become super OP. He eventually gets a party one is a former slave panada girl, a minotaur that wants to heal people, and the last one is a white spider that evolved into an arachnid girl. The last chapter is the arachnid girl being taken away by another arachnid.