I wish this had either gone firmly with, "he's an asshole, and brings this upon himself", or cut out the slavery thing entirely. As it is it's sort of uncomfortable, as on the surface she appears to be enslaving the boy for the crime of... being a tsundere in the middle of a rough patch?
Like I wouldn't judge the girl given the life-or-death circumstances, but in the shoujo context, slavery comes of as an... unnecessarily unhealthy start to the relationship.