The supporting character's harem is very normal - Chapter 134 Lathel… you are mine.

Xia Ning is betrayed by her boyfriend who wants to marry another girl from a rich and powerful family.

On Terra, everyone has a 58% chance to “Awaken” as a Traveler—a chosen few who can access mystical portals called Flumes, allowing them to travel to Genovia, a world filled with unimaginable power, chaos, and danger. But not everyone gets to be a hero.Born into a struggling family with nothing but ragged clothes and a bleak future, Aoni Thurston, a total nobody with a humiliating One-Star Potential and G- stats across the board, knows his only chance at survival hinges on unlocking his hidden ability, something which all Traveler’s are gifted “Attributes.”But Aoni’s Attribute, “Progression,” holds a secret—a power to bend the rules of his ruthless reality. Each small victory, every step forward, earns him mysterious Progress Points, enabling him to transform his weaknesses into strength. Surviving the unforgiving snows of his desolate Territory, he faces isolation, despair, and near-death, all while unraveling the potential of his Attribute.In a world where power is everything, can Aoni claw his way from obscurity to greatness, or will the system grind him into dust? His future is uncertain, but one thing is clear—everything in his world can change through his Attribute: Progression.

Konoha’s blue beast: “I want to prove that even if you don’t know ninjutsu or illusion, you can become an excellent ninja. This is the whole of my life. This is my way of ninja!”

The Roaring Emperor of Clover*: “I want to prove to everyone that no matter whether you are a poor ghost or an outcast, you can achieve great things!”

Hao Fan: “If there is any relationship between these two other than being equally inspirational, it is that my buddies were unlucky enough to transmigrate and become Rock Lee first. Because of physical defects, they couldn’t control Zach to perform ninjutsu, and then protested to the system. Afterwards, he transmigrated into Asta who couldn’t use magic…”

- Description from novelbuddy