- Family-Unfriendly Aesop: Slavery is both fulfilling and awesome! Slaves should be expected to fulfill their masters' wills, whether it be following direct orders or intuiting what the master wants ahead of time. Masters have the right to treat slaves however they want, with the caveat that the slaves as a whole will just rebel if the masters stop treating them with love.
- Jerkass Woobie: Dear lords, poor Takeya. When his father is introduced in the final chapters, we learn why he's so abrasive, and it's not pretty. When Takezou isn't being neglectful, he's being horribly abusive. Takeya spent his formative years with a parent who paid absolutely no heed to his family, often away on "research" projects and not caring about the family's important events, but when he returns home, and he always returns home at some point, he proceeds to act like a human wrecking ball, either seizing or destroying everything of value in Takeya's life, up to and including taking his girlfriend away from him. In fact, Harumi, Takeya's step-mother was once his girlfriend until his father decided to take her for himself, as a wife. Then he makes clear that he's loaning Takeya the tuition fee for the local highschool which Takeya MUST attend, and Takeya has to hold down a job in addition to that to pay his own bills, with the explicit demand that said tuition will be repaid upon graduation, AND when Takeya finds himself happy with Ren, after many trials, decides it will be a good idea to swoop in, seize Ren and launch her into orbit to die, and when Takeya runs out of his apartment after her, (having had to come to her rescue repeatedly before then) has him arrested under false charges, and then makes himself "unavailable" so that Takeya stays in jail until it's too late for him to do anything about it. What's worse, is that he considers Takeya is acting "unreasonably" for chasing after Ren in the first place. Implying that he conditioned Takeya to withdraw and sulk when someone comes trying to take his girlfriend away, like we saw when Hirofumi tried to wedge himself into Ren's life.
- OT3: Manga Only: A rare canonical example in that with all DearS now fertile, Ren, Miu, China and even Nyu, all want to participate in 'baby making' with Takeya.
YMMV / DearS