The option you're looking for is users, not user.
user makes it so that any user can mount, but only the same user can unmount. Meaning, since root is mounting it on boot, root has to be the one to unmount it, too.
users allows any user to mount, and any user to unmount.
Not sure what's on going with Pika. Who mounts the share shouldn't matter, as the folder permissions should be the same regardless.
Do you have a uid option set?