Yeah, Sander's scenes are a bit outta date. which makes things like him saying to be careful about Keros as the trickster god... while being a kitsune yourself. Like my man do you not see the 5 tails of absolute floof attached to my ass or has dementia set in.
Now, to be fair, Keros is the god of "it's just a prank bro" and general douchebaggery. Even if you've embraced the floof, you should still be careful of him. Maybe Sanders has seen the tails and that's why he's warning you.