Help, Dazai Came Out of a Dating Sim

[Dazai Osamu pairing + short sweet story + dating simulator + cross-world summoning ability + a touch of group adoration + crossover] (Worlds featured so far: Katekyo Hitman Reborn) (Still being updated; planned worlds include One Piece, Crayon Shin-chan, Natsume's Book of Friends, and Doraemon. Don't worry if you don't know them, the story explains everything ₍•ʚ•₎•ʚ•₎•ʚ•₎) ★ Duanmuyuan was a gentle, elegant, and charming young lady from a distinguished family. Everything she did and said earned her praise. One day, an irresistibly enticing dating game ad popped up on Duanmuyuan's phone, and she tapped it. A black cat with bandages wrapped around its body appeared on the screen. When choosing a love interest, Duanmuyuan mischievously picked the one that would make the black cat's fur stand on end: Dazai Osamu. For some reason, watching the little black cat bristle made Duanmuyuan feel incredibly happy. She kept playing the game, until one day her adoptive parents were in an accident in Japan. Her older brother inherited the family business and, in a good mood, arranged for his so-called “younger sister” to live in Japan, far away from him. Duanmuyuan was a dreamless slacker, and although her brother had taken most of the family fortune, what he left her was still a considerable sum. With money to burn, Duanmuyuan bought an apartment in Yokohama, Japan, to use as her temporary home. A few days later, on her way back to the apartment, Duanmuyuan ran into Dazai Osamu, whom she'd “lured in and then abandoned”... Dazai blocked the road she had to take to get home. His slightly upturned eyes slowly settled on Duanmuyuan, and his lips parted as he spoke in a gentle yet dangerous voice. “Well, well, if it isn't my girlfriend, the dear Miss Duanmu, who disappeared for several years.”