MTL - Enter the Room - Chapter 323

Finn travels to the timeline after Avengers: Endgame and obtains a system that hides one's own strength while allowing him to grow even stronger!However, he soon discovers that the system's prescribed hiding place is actually Westview!Before long, Wanda will seize control of the entire town, plunging countless people into pain and torment.Fearing exposure and determined not to give up halfway...Finn decides to act first—conquer Wanda and resolve the issue at its root.And thus, he embarks on a road of no return.Here's the cliched NOTE : English is my 3rd language so I'm not proficient in that , so if there are any mistakes please point it out to me

The daughter of a duke, the stuttering Maximilian, married a knight of lowly status at her father’s coercion.

There is a way in the world here, and the manifestation of the way is a Gu.

When people practice, they cultivate the energy of heaven and earth all over their body to drive away Gu insects and display supernatural powers.

Traveling through a year, Chen Qing finally discovered his specialness on the day he contracted the first Gu worm. He was able to see through everything about the Gu worm…

So, he started to fight steadily, step by step on the road to longevity.

- Description from novelbuddy

Our protagonist Caam is a man from Earth that was reincarnated into this world as a demon. In order to survive, he spared no effort in avoiding the sparks of battle and without noticing it, he became strong himself.