The supporting character's harem is very normal - Chapter 15: Level up?

An alien spaceship invaded and unleashed terrifying monsters on Earth. The enigmatic invaders gave humans a chance to fight back with a system and classes, but John is stuck with the NTR Rogue class.Now John's only way of getting stronger is by completing tasks related to stealing other men's women. John's life had been a cruel joke, and this new apocalyptic world might just be what he needed.----This is a “netori” story where John, the main character, steals women from others. There is no NTR towards John.Check the Discord server for illustrations: The link is at the bottom of the first chapter. Removed from here because of bots.

some day.

The heavens and worlds shook.

A huge list appeared in the sky, and the scene of counting the strange nicknames of the heavens began.

Inventory tenth, head pillar Tanjiro

Inventory Ninth: The God of the Earth Cannot Fly (Gulardo), the God of the Sea Fathead Fish (Kioka)

Inventory eighth, the second of the four Uchiha laughs – Uchiha Madara, Uchiha Obito

…

After the video is posted.

Countless dimensions were shocked.

It turns out that there are so many people with weird nicknames in countless worlds.

- Description from novelbuddy

“What the fuck? What is going on? Have I completely lost it?”

As I stare panicky at the dot unable to decide what to do, the white dot disappears and a line of text appears in its place.

[Installing files. 1% done…]

As I watch the text in shock, the percentage gradually increases. […2%...3%...4%...]

I move to the living room in a zombie-like manner, too shocked to think clearly and lie down on the couch.

“Something is wrong with me; I think I finally lost my sanity…”

[…12%...13%...14%...]

Unable to affect the situation in the least, I stare dejectedly at the percentage increase, while my mind starts exploring the possible explanations. In the end, as the percentage hits 90%, I narrow it down to three possibilities.

The first possibility is that I am in fact still unconscious and this is all a product of my mind. I pinch myself and whimper at the pain, as in my nervousness I used almost all my strength.

Nope, the first is out.

The second possibility is that I have completely lost my mind and am suffering from delusions. Hmm, I cannot exclude this, but while possible, I don’t think that this is it. The only thing out of the ordinary is that fucking line of text.

The third possibility …

[Installation successful!]

The text disappears and a new message appears in my eyes…

The third possibility … is that I gained a system. I read the message with my mouth agape at the implications.

[Welcome user, to the Perverted Daddy System!]

Fuck…

Death started her on the road of book transmigration. Transmigrating into different supporting females, snatching opportunities and men from the different worlds’ female leads’ hands. Hey, Female Lead, you can have the male lead, the supporting male is the one I want. Walking on this endless road, Xia Qiu did not expect that during these countless book transmigrations, the one she saved has always been the same person. He’s from outer space, trapped in the stream of time, with only a robot for company. Meeting her, falling for her…… However the sweetness isn’t easy. With a Boss as her man, Xia Qiu has a lot of worries. The Boss wants to bring me along as he destroys the earth, what should I do? #waiting online, quite urgent#

- Description from Novelupdates