Hmm... [Undyne would normally be a lot more aggressive about getting answers, but fish monster friend. Plus she doubts she'll be able to get much else out of him anyway.]

Well, you can have more than one companion, y'know! We've got friends and important stuff to do on the other side of this door, but if you don't mind, can we come visit you again? I'll bring food from the kitchens, we can totally hang out here instead!