They would probably approach with kindness and concern. They may offer a listening ear to the suicidal human.
Well, perhaps the twins would try to talk the suicidal human out of it. They might share their own positive experiences or stories to give the person hope.
Well, they'd probably have a stronger initial bond. Instead of starting off as rivals, they might be more like partners from the start. They'd have a natural inclination to look out for each other more directly.
If the Weasley twins met the Marauders in fanfiction, there could be a lot of interesting interactions. The twins would probably be in awe of the Marauders' reputation at first. They might learn some new spells and tricks from them. And I think the Marauders would be quite amused by the twins' modern - day take on pranks. It could also lead to some time - traveling adventures or at least stories about their different eras of Hogwarts.
The interaction could be really dynamic. The Twins are known for their banter and they might include the fem reader in it. If she's a feisty character, she could give as good as she gets. Maybe they'll have moments where the Twins show off their Transformer abilities to impress her, and she'll respond with her own skills or knowledge. They could also have some misunderstandings at first due to cultural differences, but gradually work through them.
Edward might be very protective of the twins. Since he has a close relationship with Bella, he would see it as his duty to keep the twins safe from any harm. He could also be interested in seeing if the twins have any special abilities related to his own mind - reading ability.
The Weasley twins are very much about having fun and making people laugh with their pranks. The Marauders also had a sense of humor but were also a bit more rebellious in a way. They might blend in that they would all get along well in the pursuit of pranks. But they could clash if the Marauders' more serious or secretive side, like their Animagus forms and the whole werewolf situation with Lupin, comes into play. The twins might not understand the secrecy at first.
The twins would likely have a very loving relationship with Naruto. Naruto, having grown up without parents himself, would be extremely affectionate and dedicated to his children. He would teach them important ninja values and skills, and also share his own experiences with them.
They might become more serious. Usually, they are all about pranks and fun, but under Snape's tutelage, they could learn to be more cautious and focused. For example, they would have to follow Snape's strict rules in the potions lab.
They would likely raise them with a strong sense of honor and courage. Percy would teach them about the power of the sea and how to use it for good. Annabeth would instill in them a love for knowledge and strategy. They would also train their twins in combat skills to protect themselves in the dangerous world of demigods.
First, develop interesting characters. Make the twins have distinct personalities. For example, one could be brave and impulsive while the other is more cautious and analytical. Then, create a tense and mysterious setting for the kidnapping. Maybe it's an abandoned warehouse on a stormy night. Also, build up the motivation of the kidnappers. Are they after ransom, revenge, or something else? This will keep readers engaged.