After Making a Pact with a Shadowy Evil Spirit

After making the contract, Fu Ning felt that thing had latched onto him. Whenever he woke up in bed, cold sweat would soak his entire body; At night, something sticky and soft would silently crawl over him; In the bathroom, warm breaths would brush against him from the collar of his shirt; In class, invisible hands would idly play with his ankles; As he walked down the street, a tempting voice would whisper in his ear: That person seems to have designs on you. Shall we... teach him a lesson? They say that people possessed by an evil spirit like this either die or go mad, and fewer than one in a hundred survive. Good thing he was already a little off to begin with. Hehe. Attacker's POV: He was the master of evil spirits, destined never to enter the cycle of reincarnation. When he awoke again from a long slumber, he sensed an extraordinarily tempting presence. He liked this scent. He wanted him. * The Anomaly Management Bureau had been exceptionally busy lately, with one "anomaly portal" after another appearing. Amid all the signs, they began to take notice of one person. The young man had delicate features and seemed gentle and obedient. When they approached him, he pointed at himself in confusion. "Me?" That bewildered, innocent expression looked about as harmless as anyone could be. The people at the bureau: ...Well, now we're not so sure. Much later, looking back on it all: As expected, the prettier they are, the better they are at lying! ※Dark, scheming green-tea attacker x seemingly innocent but secretly twisted yandere receiver ※The two parties to the contract are something like a symbiotic master-and-servant, exclusive partners, mutually covetous, and [censored] relationship ※Since neither of them is particularly normal and both have frequent episodes, no guarantee of sound values, only a guarantee of two equally matched leads ※A faux infinite-flow story, with a very chaotic worldbuilding setup Theme: Finding oneself again.