Spider - Man would probably be really curious about the Demon Slayers' powers. He might be constantly asking questions about their breathing techniques. And the Demon Slayers would be amazed by Spider - Man's superhuman abilities like climbing walls and shooting webs.
Tanjiro would likely befriend Spider - Man quickly. He would see Spider - Man as another person fighting for good. Spider - Man, on the other hand, would be intrigued by Tanjiro's sense of smell and how he can detect demons. They could exchange stories of their battles and learn from each other's fighting styles. The more hot - tempered Demon Slayers might initially be a bit wary of Spider - Man, but once they see him in action against demons, they would accept him as an ally.
The interaction between Spider - Man and the Hashira would be quite interesting. The Hashira, being the top Demon Slayers, would be both impressed and perhaps a bit jealous of Spider - Man's unique powers. Spider - Man would respect their skills and authority. He might try to learn from their strict discipline and training methods, while the Hashira could gain new perspectives on combat from Spider - Man's unorthodox fighting style that combines acrobatics and web - based attacks.
Well, if Spider - Man met Ruby, he'd probably be intrigued by her enthusiasm and her weapon, Crescent Rose. Ruby, in turn, would be in awe of Spider - Man's powers. They might start off a bit cautious around each other, but once they realize they're both fighting for good, they'd become friends quickly. Spider - Man could teach Ruby some new acrobatic moves, and Ruby could show Spider - Man how to better use his environment in combat like she does in the RWBY world.
The interaction would be really interesting. Spider - Man, being from a different world, would bring a new perspective to the RWBY characters. For instance, he could teach them about his concept of 'with great power comes great responsibility'. Weiss might be a bit snobbish at first towards Spider - Man, but as she sees his heroics, she would come to respect him. And Spider - Man would have to adapt to the different social hierarchies in the RWBY world. He might find the Faunus situation quite different from what he's used to in his own world and try to help promote equality in Remnant.
Well, Peter Parker might be really curious about Ladybug's powers. He'd probably ask her a lot of questions about how her Miraculous works. Ladybug, on the other hand, would be interested in Spider - Man's scientific gadgets. They could exchange knowledge and techniques.
Scarlet Witch could potentially enhance Spider - Man's physical abilities using her magic. She could make his strength even greater or his speed faster for a short period. In return, Spider - Man could protect Scarlet Witch from close - range physical threats. His ability to swing around the city quickly could also be useful in getting her to different locations where her magic is needed.
One interesting crossover could be Spider - Man using his web - slinging abilities in the Demon Slayer world to quickly move around and help the Demon Slayers. He could use his enhanced strength to take on powerful demons that the Demon Slayers might struggle with.
Harry would probably be a bit of an outcast at first. The other students at Hogwarts might not understand his strange powers. Hermione would be curious and try to research if there was any magical explanation for it. Ron might be a bit jealous at first but then come around. And the teachers, like Dumbledore, would be very watchful. He would likely try to guide Harry in using his powers for good and not let them cause chaos in the wizarding world.
Spider Man would probably be very protective. He'd use his agility and strength to keep the kid out of danger. For instance, if they were in a fight scene, he'd quickly web - sling the kid to a safe place.
The characters interact in various ways. Spider Man is often the central figure, and the female characters in the harem might start off as just friends or allies. For example, Mary Jane might be initially jealous if other characters join the harem. But as the story progresses, they learn to work together and support each other. They might train together to fight villains, like Spider Man teaching some of the less experienced characters new combat moves.
The characters could interact through a magical portal that connects the two worlds. Harry Potter characters could enter the Demon Slayer world and vice versa. For example, Hermione could use her vast knowledge of magic to help the Demon Slayers understand the more complex aspects of the demons they fight.
Supergirl's super strength and invulnerability could provide a good defense for Spider - man. When they face really tough opponents, she could take the brunt of the attacks. Meanwhile, Spider - man's agility and ability to climb walls could help them access hard - to - reach places during their adventures. His spider - sense could also give them an early warning of danger that Supergirl might not detect right away with her normal senses.