“Bull” shit is a joke because Willful’s animal is the bull.

Wynn: I still wanna know what kinda Bull shit made the bird go to you.

Siyav: You really don’t believe I didn’t do anything?

Nievu: Apparently Siyav’s lucky. No magic or strength needed.
Wynn: Yeah I guess th-

Wynn: He is.

Shirley: It’s uh.. much colder than I thought it would be.