Star Nun: "Oh, sorry Father Monk." Father Monk: "It's fine. I can take it, in contrast to brother Frond who completely lost it over the "Brownie Chair Surprise" by that little girl with the Bunny Ears."
Well, they're a robot assistant who's duty is to provide japari bun to friends who live in various environments and places and a replacement to look after the friends, so they should be able to swim at least in order to fulfill their duty