Novel & Cerita Harem Anime Meaning

Cruz, “Do you mind explaining this ‘harem’ to me?” “It’s just some silly game that some of our alpha students are playing,” tumatawang sagot ni Mrs. Cruz. “They try to recruit omegas to their so-called ‘harem’, parang barkadahan lang ito na alpha ang leader, the more omegas join their group or ‘harem’, the higher they are in the alpha hierarchy.” “Your school has such a tradition? Isn’t this a blatant display of alpha chauvinism where they objectify omegas as something they can ‘collect’?”

"What about it? Your parents must be smart enough to give you such a unique name." Muntik nang mabulunan si Allen. Tinungga niya ang juice na hawak-hawak nito. "Anong kakaiba do'n? Pinangalan ako ni Mom sa isang Shinigami character sa anime! Blessing in disguise na nga na dinagdagan niya ng Allen ang pangalan ko kung hindi, ewan na lang." What kind of anime series is he referring to? I'm not fond of those things.