Who is 自分？

「自分」 is a commonly used pronoun but it's not always clear exactly who is being talked about. Depending on context, or more importantly regional dialect, 「自分」 can be a first person, second person, or third person pronoun. Dictionaries usually list a third person definition like [one] or [oneself], but in my experience, third person usage is the least common. While not a fixed rule, 「自分」 is usually first person in western Japan and second person in eastern Japan, but that's not important. As a general rule, you should probably avoid using 「自分」 because of problems with ambiguity until you've had enough direct experience with native Japanese usage to understand some of the nuance. There are plenty of other usable and more specific pronouns for first person ( 私、僕、俺、アタシ、我、これ), second person (あなた、君、お前、てめぇ、それ), and third person (彼、彼女、あの人、その人、この人、あれ). But if you like to exude an air of aloofness, you can go ahead and use 「自分」 for everything. As long as you can use it with confidence, you don't really need to worry about other more specific pronouns. This does mean that sometimes, or often it will be unclear who or what you're talking about, but one of the magic things about the Japanese language is that there's lots of ambiguity built in because everyone is supposed to all be thinking the same thing all the time. Even if the people you are talking to aren't sure what you're talking about they will usually make an effort to try and understand context, and if they can't figure it out, they will likely think it's their problem for not understanding something that should be implied, and that you are smarter than they are. Or an asshole. But they won't know which it is for sure, so they won't complain. Or try and correct you.