[Himura]

can't return to temple?...

You should just use the recall stone to get back to temple...

In the werewolf den you should find the note point to a particular residence in Port Llast. You need to talk to the cleric inside the temple, he will ask you to kill the werewolf.

To be simple, the werewolf is in one of the house in Port Llast. However, he won't be there unless you return to the cleric and tell him who the werewolf really is. I think you need to get the dairy from Sir whatever in the cave south of Port Llast to prove that.