The Sinful Life of The Emperor - Chapter 3: Making Out In Shower

Violet skies, a world undergoing massive changes, a deficient moon, interlinking voids…
When the world experienced a cataclysmic event,the majority of living things ceased to exist. Although humanity survived by hiding in the last safe zones, humans had to face mutated dire beasts and colossal source beasts that could break through the space barrier and enter the earth at any second.
Luo Yunyang, a young man who grew up in those calamitous times, obtained an attribute regulator and set out to walk the path of supremacy!

- Description from novelupdates

Leiyin accidentally crossed into the One Piece World, and accidentally obtained the Naruto System.

When necromancers perform a great ritual to summon an undead servant, they bring a powerful vampire into their world. And now, their fate is sealed as food, but for Klaus, this is just the beginning of his adventure. In a cruel world where people will do anything for power and immortality, he is already very strong and immortal, so what's left if not start a family and have fun stepping on arrogant people through the way?

[No fixed CP + wear books + brain hole cool text + women disguised as men + group pet]

Gu Lan crossed over and became the cannon fodder of the original book disguised as a man, counterattacked the protagonist of the original book who slapped her face, and lived in a dormitory full of sickly beauties.

Until one day, she discovered that her roommates were villains from other horror novels. After discovering the secret, Gu Lan thought she would be killed, but her roommates all looked at her strangely… Contrasted with cute Zhengtai, sickly and beautiful boy, split personality school girl, cold and stern school bully, romantic and noble son who plays Shura every day field.

- Description from novelbuddy