The supporting character's harem is very normal - Chapter 23: Contract…

An Earthling soul awakens in the ailing body of Loryarc Lapizburn, a disabled young man betrothed to the second daughter of the notorious Hallmeavan Family.The Goddess of Kiss blesses him with a unique ability known as the [Kiss for More] System, which allows him to gain skills by kissing.Can this new soul confront the dark secrets hidden within the Hallmeavan bloodline using his System?What about the chaos in his predecessor's county, where the branch families are constantly at odds?Why did the Goddess of Kiss choose him to receive this System?Kiss, kiss, and keep kissing...What awaits him in the end?Anything is possible... through kisses!

Yang Yan found himself becoming a corpse. But before he could stay for a minute, the lid of his coffin was opened.A stunning face appeared in front of him.Leng Biyue!As the Holy Maiden of the Fairy Maiden Sect, she possessed the quasi-empire bloodline!Blood spilled from the corner of her mouth, fell, and landed on Yang Yan's face.His eyes opened!“The Sword Dao Emperor, who was buried for 100,000 years, has come to life once again!”

Nagasawa crossed to Naruto Universe and was bound to Konohagakure.

If Konoha is severely damaged and destroyed, Nagasawa’s lifespan will be reduced.

He panicked at the thought of the upcoming Nine-Tailed Demon Fox’s attack , and the thought of Konoha getting destroyed left him in despair.

Fortunately, while bound to Konoha, he can obtain templates of powerful characters.

At the beginning, He got the Whitebeard template! Since it’s the Whitebeard from the Summit War of Marineford, he can use Tremor-Tremor Fruit’s ability and Haki.

Facing the Tailed Beast Ball, which terrorized Konoha Shinobi, Nagasawa leaped and shattered the Tailed Beast Ball with one punch!

- Description from Novelupdates

Shao He, heir to a family renowned for medical and poison skills, a top special agent of the 21st century, unexpectedly transmigrated into the body of a pathetic Madam Marquis who had been tortured to death! And on that very night, she was thrown into the Mass Burial Mound!Looking at the newborn in her arms, Shao He resolved to live a splendid life in this foreign world!From then on!She was the Divine Doctor who aided the world!She was the fearsome Poison Queen!She possessed wealth to rival nations!She was also an astonishing scholar!And the Marquis, filled with regret, wished he could kill himself on the spot, “He'er, I was wrong, you...”“Shut up, I am now the Empress!”