Summary by Salem
The owner used to have a yukkuri pet, but that pet had children with stray and starts looking down on him and call him slave. Angered, he beat them, pull their tongue out and throw them out to the garden. That time he realized, rather than the happily smiling yukkuri or the arrogant yukkuri, he think the miserable yukkuri is the cutest.
He then took a set of yukkuri from his friend whose in the same situation as his (made child with stray and turns into scum).
He turned both parents into compost yukkuri and put them at a corner of the park then have the KoMarisa as pet in the garden. That Marisa is dirty and full of scars like stray. He call this playing stray. The only difference is Marisa won't die in hunger because she can eat the poo poo from her parents.
He would sometime show Marisa cakes but beat Marisa before she can touch it. Other time he wear Factory worker cap and chase Marisa, spraying her with not extermination spray (made to kill) but with the yukkuri protector group's spray (made with the notorious smell of yukkuri yukari and other uneasy smell) that will make yukkuri run away and hide somewhere unseen by human.
This way, Marisa is made to never have any self confidence and gloomy everyday with dirty body smeared with dirts and her own excrements. The moment she sees human, Marisa would shiver in fear and leaked pee pee.
He's hoping that the next generation would be even more stray like.