I thought it was monster kid and Alphys. There's one conversation from a brother, asking his sister to make a wish, and then him wishing for his sister.
It isn't any better than any other of the cancerous fandoms on here. It just so happens that most of FJ has hopped on the bandwagon this time.
Honestly it's cool that the artist took time to make this, but I'm a cynical nihilistic bastard and it annoys me because I don't give a **** about these ****** looking skeletons or how many "feels hurr dur" it gives people.
Well someone posted a graph once, which showed 2 circles (not overlapping). The one circle had "people who played undertale", the other had "people who hate undertale". I can realy relate to this, since I hate almost every bandwagon here, from animuuh to vidya, not undertale not excluded, but hey gave it a go. I now realy love this game, but I don't agree with this 'happy ever after fandom world' people create. It's just that the game has more effect on the one than on the other, but everyone will change their minds after playing it, at least a bit.