How is this supposed to be funny, again..? I guess it could've worked if Teru was a known masochist, but this isn't the case here.
Getting tortured and literally brainwashed; he gets treated like dogshit, yelled at, berated, hit, and even betrayed again by Tanya...Paging doctor humor, you bailed your shift here.
This chapter honestly comes across as the author's personal fetish coming to light, rather than a fitting plotpoint to this story.