Brave Soul of Evil Supremacy - Chapter v2ex8: Volume 2 Extra 8 Urza's and Levienna's Adventures (Part Four)

A fluffy, sweet modern GL story about a mature older women and a cute university student.

However, he did not know that he was not raising just a harmless pet, but a biological weapon secretly made by the government… a real monster.

As a former librarian, Rand felt that he had been living an ordinary life, the one that he had reclaimed unconsciously every single day.

Recently, he has been a little upset because the pet fish he accidently brought home to raised seems to have undergo some strange changes

Well, it turned into a merman.

- Description from Novelupdates

After her rebirth, Rita vows not to repeat her past mistakes. This time, her first priority is to stop her brother, who is about to marry into the Lopez family, from participating in the initial game beta test. In her previous life, she was deceived by this scheming brother until her dying breath. It was only at the end that she realized she was merely a villain in a male-oriented novel about a live-in son-in-law, with all the malice and manipulation orchestrated by him behind the scenes. In this life, Rita decides to change the rules of the game. She will stay in the shadows and seize all the opportunities meant for the male and female leads. By participating in the beta test and re-selecting her abilities, she systematically dismantles the protagonists’ advantages, all while making them believe she’s on their side. Rita has no intention of harming innocent people, nor is she a selfless saint. In this game, she works with the authorities for mutual benefit, all to achieve her ultimate goal—becoming the true master of her fate.