The villainous daughter of the Duke, needs a hero - Vol 2 – Chapter 11: His Big Mistake

Cassian Ven Dyke, the bastard son of a powerful ducal family, grew up in the slums of Veldora under the care of his father figure, sword master Russel. When Russel passed away, Cassian was left with only a silver necklace as his inheritance. After putting it on, Cassian was attacked by three psychotic thugs who tortured him in an attempt to steal the necklace. Refusing to give in, Cassian was ultimately stabbed through the heart with the very same necklace. Instead of dying, he mysteriously vanished as the necklace lodged itself in his heart. Just before disappearing, he heard an eerie message echo in his mind:[True mana detected. Origin: Human...][Human detected. Compatibility with system: Confirmed.]

Witnessing her boyfriend cheating on her with her bestie, Shiyao was so angry that she went to a pub for fun and met a man, who was really a piece of work. After a crazy night she fled away, but was embarrassed to know that the man she slept with was her boss You Ze.
Jesus, give her a break!

- Description from Novelupdates

In countless worlds, mysterious doors appear, leading to an ordinary-looking convenience store. That is, until you see who’s inside.An immortal cultivator ponders over instant noodles flavor, an ancient demon sips a cola, and a primordial beast carefully holds a bag of potato chips. Beings who could shake the heavens stand quietly in line, waiting their turn.At the counter, a young man scans their purchases. No one knows where he came from, but all understand one thing. In this store, rules must be followed.Welcome to the Dimensional Convenience Store, where even the greatest existences must check the price before they buy.

[You have become the master of the Warden Mansion.][Your first quest is to refine mana from one of your maids by having intercourse with her.]When nineteen-year-old Jett Talon suddenly wakes on an emperor-sized bed, he finds himself lord of a mysterious mansion where countless gorgeous maids stand ready to serve. His first companion is Mia, a blonde elven maid who checks his every box. After making love to her, Jett gains mana, unlocks legendary powers, learns his duties as Master of the Warden Mansion, and uncovers its hidden secrets.