Rats don't bother him a whole lot, but he's far from being fond of them, so having to catch them alive and then tossing them into a bag is not his idea of fun. He doesn't even think getting cake is worth it, yet somehow here he was catching rats for free cake.

And the reason why he was doing it was standing a few feet away practically cooing at a rodent.

"Shepard... are you really giving advice to a rat?" he asks from where he's standing, hand on his hip, the other one grasping the end of his bag to make sure the rats in it don't get out.