彼・彼女・あいつ

About

Japanese has various third-person pronouns. Three common ones are 彼かれ ("him/he") 彼女かのじょ ("she/her") and あいつ ("they/them").

彼かれ and 彼女かのじょ can also refer to "boyfriend" and "girlfriend". Although this usage is usually distinguished through context, 彼かれ often becomes 彼氏かれし when referring to "boyfriend", but in casual settings, just 彼かれ may also be used.

こいつ, そいつ, あいつ, and どいつ are a set of こそあど words that can be used as third-person pronouns. They are very casual and can be rude when used outside of close friendships.

こいつ, そいつ, あいつ, and どいつ can be used to refer to inanimate objects and scenarios as well.

Summary

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  彼かれ ("him/he") 彼女かのじょ ("she/her") and あいつ ("they/them") are Japanese third-person pronouns

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  あいつ is part of a こそあど set, is very casual, and can also be rude