There's a fair bit more to it than that.



Truthfully, this ship makes more sense than the vast majority of Undertale ships: He hungers for good baked goods. She hungers for the tea to complete her tea party. She is driven to fight for her people (the spiders) to the point where she has been isolated from the rest of the community. He was driven to fight for his people (all monsterkind) to the point he has been isolated from his wife. He wants a family again. She has a HUGE family. They are both scary at first, but have good hearts and intentions when you get to know them. Also, as a master gardener Asgore would be intimately aware of how useful spiders can be and would respect and care for them (as any good gardener would)....a fact which would definitely get Muffet interested.