I'm a Siscon, but I Accidentally Became Everyone's Favorite

Jiang Man transmigrates into an old-fashioned melodramatic romance novel, becoming the heroine's little sister, who is only five years old. In the original story, Jiang Man's older sister, the heroine, is caught in a torturous love triangle with three men. After a series of emotionally devastating events, the story ends on an open note. Jiang Man: ...I don't get it. I'm absolutely shocked!!?? The heroine is very good to Jiang Man. She's beautiful, sweet-voiced, and an incredibly capable top-tier actress. Why would she get involved with three scumbags? No way. Jiang Man resolves to protect her sister. When the first male lead, a domineering CEO, tries to force the heroine into a relationship, Jiang Man immediately calls the police so they can give him a proper talking-to. When the second male lead, a scheming actor, tries to tie the heroine down with a dating contract, Jiang Man pretends to have a stomachache, ruining his plan to sweet-talk her. The third male lead is a calculating director. He tries to win Jiang Man over to get closer to her sister, but Jiang Man immediately shouts, "Uncle!" and rejects him as emphatically as she can. In short, Jiang Man is mischievous and does everything she can to keep her sister away from the three male leads. She never expected that the men wouldn't dislike her for being such a handful. Instead, they start sincerely treating her well. Jiang Man: ??? These three scumbags still haven't given up. I have to stay on my guard! I must protect my sister! Jiang Man clamps a lollipop between her teeth and glares fiercely at the three men in front of her. The three men are so charmed by her adorable expression that they resolve to give her even more fatherly love (?) [Bonus Scene] The male leads decide to take the indirect route to win the heroine over. They introduce their nephews, nieces, and younger brothers to Jiang Man. The kids will become friends, and then the men can use that to get closer to her. After meeting Jiang Man, all the children grow fond of her and become very close to her. The mischievous nephew says, "Manman is my little sister from now on. I'll take her along to play." The somewhat aloof nephew says, "Mm, Manman is my little sister too." The gentle younger brother, who loves fairy-tale books, pauses. "...Mm, Manman isn't my sister. She's my childhood sweetheart." #Someone here is acting weird. I won't say who# The heroine, a sister-complex who has been listening to the four children the whole time, reaches out and strokes her younger brother's head. Her smile is gentle, but a little frightening. Sister: I feel like clay-pot rice tonight. You're the ingredient, kid! Reader's guide: 1. There is a couple. Choose from among the three childhood friends. 2. To be added. Theme: Do your best to protect the people who matter.