It's definitely yuri, since there's clearly love between Keine and Mokou. They don't have to be kissing to establish that. Plus, I'm pretty certain the reference to the moon is alluding to the famed translation of "I love you" that appears in many stories.
But yes, it's kind of SoL-ish in that it's a story about what each are doing while they're separated. Mokou's mellowed a lot, and is able to tolerate Kaguya helping her pass the time. This seems to be one where Kaguya honestly cares about Mokou's well being, even though she conceals it beneath many layers. She's making sure her friend, indeed one of the only people who could be her friend, is okay.