How Did I End Up in a Hand-Seal Class When I Just Wanted to Learn Sign Language?

Lu Yin, a stand-up comedian in his previous life, suspects he must have had eight lifetimes' worth of terrible luck. After being reincarnated, he has no skills whatsoever and has even become mute. Then monsters and demons show up at his door, claiming they want to make him the Lord of the Mysteries? Lu Yin: I still want to be human!