Valkyries Calling - Chapter 1: The Oath Beneath Basil’s Tomb

Yo, Hi! I’m Frank, I made a deal with a demon to pay me some money for receiving a guest for a few days every week.
I had no idea about what I have done.
On May 1st, Conan ‘the God of Death’ came to my house. I was forced to let him in and we get involved in a criminal case.
On May 8th, Bruce Wayne ‘Batman’ came to me. I was forced to follow him to fight crime.
On May 16th, Hannibal Lecter, The Silence of the Lambs, came to my home. I can only say that I really can’t stand my guests.

- Description from Novelupdates

The apocalypse has arrived, unleashing monsters across the globe.Jeremy, a high school student with a past life as a mercenary, awakens to an SSS-tier ability known as “The Eye of Omniscience.” This power allows him to perceive hidden cues invisible to others.[There's a silver treasure chest in the room to the left. Opening the chest with your foot guarantees a 100% chance to obtain a silver-grade item!][There's a hidden boss in the girls' bathroom. Defeating it with a sanitary pad will surely drop a rare skill scroll!][Slapping the job-change statue 99 times during your job change will unlock the hidden class “God Desecrator”!]While the rest of humanity is still living in fear, Jeremy has already obtained various god-level rewards thanks to his Eye of Omniscience.While others are still figuring out how to survive the apocalypse, Jeremy has already reached the pinnacle of humanity, confronting the gods themselves!

In the vampire-ruled kingdom of Mildelar, the Blood Games stand as the ultimate form of entertainment—savage battles between familiars, humans bound to their vampire masters through blood pacts. Far more than mere spectacles, these brutal fights determine the prestige of noble families, shaping their power and influence across the realm. Lyon, a young human saved from death by a blood pact with the alluring Arya Valakys—one of the king’s daughters—is unwillingly thrust into this cruel world. Bound to his mistress, he is forced into relentless battles to elevate her standing.Lyon, however, stands apart from other familiars. While they derive their strength from the fear of punishment, he draws his... from having dirty thoughts about his mistress!