Really cute chapter. Side couples always seem to be more interesting than the main pairings, and these two are no different.
The mysterious power of side-couples makes them appealing, is it because they aren't a focus? Like something happening on the side on it's own as the main focus tends to move on? Is it giving some depth the side characters involved?... I don't really know how to pinpoint it, but it certainly does work :p
I think it's because the writers feel like they can have fun with them while the main characters have to be written to attract the largest audience possible.
I found this chapter adorable, but was rather rather dissapointed that we didn't get to see more of Kanna. Though, I suppose she'd have to be temporarily written out to give the other characters some screentime. Her spastic personality does seem to overshadow everyone else's.