Marisa works with (or competes with, depending on how you look at it) Reimu at resolving the youkai attacks (or "Incidents", as they are called), but for different reasons. Marisa has no legacy to uphold. She does not fight monsters because she has an outside obligation to do so. She does it for her own reasons. Specifically: She stands up against powerful Youkai because she's powerful enough to do so, and most humans aren't. She does it because humans are almost always outmatched in terms of magic. Youkai are usually stronger physically, almost impossible to kill, and have a long history of eating or otherwise severely inconveniencing humans, and Marisa knows that if she lets them do what they want, humans might start getting killed. Despite her light hearted attitude, she is very much playing to win.
Marisa's best friends are probably Reimu and Alice. Reimu she views as fellow youkai exterminator, but also a bit as a rival, so there's sometimes a slightly competitive edge to their interactions. Alice, on the other hand, is another magician, so Marisa gets to talk shop with her in a way that she can't with Reimu. She also tends to bring out the rude punk in Alice, so if she can manage to get her to go outside somewhere, they end up egging each other on and causing WAY more chaos than they would on their own.
Beyond them, Marisa is actually more tolerant of youkai than Reimu is. She has no hesitation about hanging out with them, since she doesn't have to uphold the dignity of a shrine, so she is probably more likely to be seen associating with them. Not least of all because it's a good way to keep an eye on them, and because powerful youkai frequently have way cooler stuff than humans can get their hands on. Rinnosuke's weird outside world items, Patchouli's magical library, oni wine, and all kinds of other stuff that tempts her constantly.
Treading into headcanon here, but I think Marisa is also more willing to associate with youkai because she's a magician and it's likely that she herself will become one. Some day down the line, she will do some kind of big spell and replace her frail human body with one powered entirely by magic, and become a being similar to Patchouli. Three hundred years later, Yukari has become even more inactive, and Marisa has taken up the job of "that one annoying but horrifyingly powerful Youkai that annoys the Hakurei Shrine Maiden."
Re: Revision
[Angrily withdraws app in a huff.]*ahem*
Marisa works with (or competes with, depending on how you look at it) Reimu at resolving the youkai attacks (or "Incidents", as they are called), but for different reasons. Marisa has no legacy to uphold. She does not fight monsters because she has an outside obligation to do so. She does it for her own reasons. Specifically: She stands up against powerful Youkai because she's powerful enough to do so, and most humans aren't. She does it because humans are almost always outmatched in terms of magic. Youkai are usually stronger physically, almost impossible to kill, and have a long history of eating or otherwise severely inconveniencing humans, and Marisa knows that if she lets them do what they want, humans might start getting killed. Despite her light hearted attitude, she is very much playing to win.
Marisa's best friends are probably Reimu and Alice. Reimu she views as fellow youkai exterminator, but also a bit as a rival, so there's sometimes a slightly competitive edge to their interactions. Alice, on the other hand, is another magician, so Marisa gets to talk shop with her in a way that she can't with Reimu. She also tends to bring out the rude punk in Alice, so if she can manage to get her to go outside somewhere, they end up egging each other on and causing WAY more chaos than they would on their own.
Beyond them, Marisa is actually more tolerant of youkai than Reimu is. She has no hesitation about hanging out with them, since she doesn't have to uphold the dignity of a shrine, so she is probably more likely to be seen associating with them. Not least of all because it's a good way to keep an eye on them, and because powerful youkai frequently have way cooler stuff than humans can get their hands on. Rinnosuke's weird outside world items, Patchouli's magical library, oni wine, and all kinds of other stuff that tempts her constantly.
Treading into headcanon here, but I think Marisa is also more willing to associate with youkai because she's a magician and it's likely that she herself will become one. Some day down the line, she will do some kind of big spell and replace her frail human body with one powered entirely by magic, and become a being similar to Patchouli. Three hundred years later, Yukari has become even more inactive, and Marisa has taken up the job of "that one annoying but horrifyingly powerful Youkai that annoys the Hakurei Shrine Maiden."
[Editing my app to include all this as well.]