The supporting character's harem is very normal - Chapter 387 Blood King vs. Darkness King

When gods gather, lightning will strike and the earth will move. Immortals! Which of the numerous way to immortality should one follow? Immortals are hard to seek, but why should immortals hide? Heaven has no mercy, but humans have emotions, and these emotions hinder the road to longevity!

Train the inner self to stay calm, train the external body to be resistant, then cross the three continents and four seas alone, and fight valiantly with demons and devils! With the heavenly baton in hand, raid the devils and demons without any resistance! Take one step to cross nine stars and chase the sword in the dreams! Traverse a thousand li of river and mountains in a single day! The exceptional beings do not mix with the ordinary! Within the universe, where can one find an obstacle! Moving like a dragon, with talent like a phoenix! The heavenly Daos and stars will guide one’s way!

- Description from Novelupdates

When a fantasy kingdom needs heroes, they skip the high schoolers and summon hardened Delta Force operators.Lieutenant Cole Mercer and his team are no strangers to sacrifice. After all, what are four men compared to millions of lives saved from a nuclear disaster? But as they make their last stand against insurgents, they’re unexpectedly pulled into another world—one on the brink of a demonic incursion.Thrust into Tenria's realm of magic and steam engines, Cole discovers a power beyond anything he'd imagined: magic—a way to finally win without sacrifice, a power fantasy made real by ancient mana and perfected by modern science.But his new world might not be so different from the old one, and the stakes remain the same: there are people who depend on him more than ever; people he might not be able to save. Cole and his team are but men, facing unimaginable odds. Even so, they may yet prove history's truth: that, at their core, the greatest heroes are always just human.

Thalion’s life as a marine biologist was modest in wealth but rich in joy and fulfillment. The arrival of the system sent everyone on Earth into a tutorial while merging it with four other planets. Not everything was bad, though. The system granted people magic and even ways to defy time itself. For now, everyone struggles to survive the tutorial, which has become more of a slaughter trial than a learning experience.If you like stories with Shapeshifters and Bloodmages. Check this out!!! A post-apocalyptic LitRPG series inspired by The Primal Hunter, Defiance of the Fall, and Elden Ring.Release Schedule:Five chapters a week. (Wordcount between 2,000 and 3,000)Also, this novel is posted on Royal Road and Patreon with Patreon being up to 60 chapters ahead of the Royal Road release.What to expect:-Multi-POV Storytelling but mostly main character-Adaptive Magic System – The magic evolves based on the wielder, making every spellcaster’s abilities truly unique.-No harem-Entities Beyond Humanity-Expansive Worldbuilding