The supporting character's harem is very normal - Chapter 313 What if I’m not generous?

One day, a tower appeared in the skies of all the major cities…

In the blood-soaked world of Magus , Aizen, a young man from Earth, finds himself thrust into a brutal reality where Sorcery reigns supreme. Once a lowly servant, despised and humiliated, Aizen hid his true intentions beneath a mask of submission. With each insult endured and every drop of blood spilled, he sharpened his resolve, guided by the mysterious Wisdom System.

There was nothing left to lose in his life.He had lived as a hero. He had started at the bottom and worked his way up to the top, at the end he become the best, yet he had always been betrayed by those he had tried to protect.Humanity did not deserve his protection.When everything went out and he could no longer even hope to beg for his life, he could do nothing but look up at the blood-red sky among the corpses of demons and angels.He wished for one more chance, just one more chance.And when that chance was given to him, he swore that he would change everything. He would no longer be a hero to save people, but an anti-hero to save the world.Sacrificing hundreds of people to save an elf, poisoning hundreds of people to save a group of half-demons.He didn't care about any of that anymore, he would protect those he cared about and send everything else to hell.Not even the gods or goddesses could stop him.

Damien reveals an ugly truth.His sister and only family, Ahara, leaves the house every midnight whilst he's asleep—a time that he soon discovers is when man-eating beasts named Rouges start hunting for prey.Unable to question her directly, he decides to investigate her and quickly figures that Ahara isn't human but rather, a vampire hero who saves them from beings like herself coming from a world she calls Gibbous—a place where entities like vampires, wizards, and beast shifters alike reside. What’s more, he also learns that the real reason behind his parents' death was the leader of the Rogues, who's rumored to have escaped after Damien’s father almost killed him.A series of fateful events lead to Damien’s long-lost power reawakening in him, and he finds himself with no choice but to return to Gibbous, a strange world where power means survival, and weakness leads to death. As such, Damien enrolls in an academy to train his newfound abilities with one thing in mind...Becoming more powerful.However, he soon discovers that the path to power is one filled with troubles and pain, and he isn’t alone in this lust for more at the academy. It’s a bloody competition against time and formidable opponents, and only those willing to sacrifice their comfort are the ones who can attain it.With a deadly foe lurking in the shadows somewhere and a strong desire to protect his sister, Damein has no choice but to fight.The only way is up, and he is going to be standing at the top of them all, ready to counter any enemy.