Yeah judging from the first part's images and some of the translations (calling him Slave, etc), they were shithead strays he picked up and spoiled, I'm assuming for this exact payoff of revenge torture.
Sounds like the kos were born shitty, too, so in the end they're all getting what they deserve, I suppose.
Can it be called revenge ? He's preparing for this "justice" and deliberately spoil them.
Anyway, the Ko-Marisa is average. She doesn't complain all that much, unlike the Ko-Reimu who quickly want to kill their useless mother.
Setting them up for failure.
A rose by another name, m'boy. A rose by another name.
Ah I forgot I bought cake!So, so ah right! Reimus stomach are poking so want sweet sweets!Mister show is enough! Reimu is bored!You guys want to eat short cake right?Convenience store sweetYunyaaaaaShweech-sweechs!?
Weimu will each!
Huwwy up and bwing it here okay!!