There Is No Limit to My Adaptability

Lu Yuan is an ordinary high school student. His originally peaceful life was broken by a strange post, and mysterious emails followed. Don't trust anyone! Everyone can be a monster! He didn't take it seriously at first, thinking it was a prank, until his childhood sweetheart went on a date with him, and on his way home in the evening, he revealed a devilish face. When Lu Yuan thought he was about to die, a female hero came down from the sky and saved his life, asking him to take off his pants... In a dangerous world surrounded by demons, Lu Yuan was lucky enough to awaken the system, which can adapt to various abilities and attacks infinitely. When the adaptability reaches 100%, he can also completely copy the abilities. The disadvantage is that he needs to endure to become stronger. [Has withstood 'venomous fang erosion' ten times, adaptability is 100%, successfully learned! [Have withstood 'God's Punishment' five times, adaptability is 100%, and successfully learned! [I have withstood the 'Sen Luo Wan Xiang' three times, the adaptability is 100%, and I have successfully learned! ... Lu Yuan occasionally ponders, why is this ability increasing?