[Raiga]

Spoiler for Fanart:

Sonata concludes that Mimori is an "M" because that's the first letter of "Mimori".

So she proudly announces to Linda that Makoto is also an M.

After Makoto explains to Sonata what being "M" actually means, Sonata is confused. Why would someone want to be teased or hurt?

Linda says, "It's not that hard to understand. Makoto's just like that."