Learn Finnish: Hän sotkeutuu aina johonkin konfliktiin. - He always gets mixed up in some conflict.

The verb sotkeutua (to get mixed up in, to entangle oneself in) is a verb of interference. Just like osallistua (to participate) or puuttua (to intervene), it requires the illative case because Finnish conceptualizes this action as a movement into a situation, rather than a static state.

How is the word johonkin formed?

It is the illative form of the pronoun jokin (some, any). You take the base jo-, add the illative ending -hon, and then attach the fixed clitic -kin at the very end. The -kin suffix always stays at the absolute end of the word, regardless of the case ending.

I recognize the root of sotkeutuu from the word for mess (sotku). How does the verb suffix change the meaning here?

The base verb is sotkea, which means to mess something up (an action done to a direct object). By adding the automative suffix -utu- to make sotkeutua, the verb becomes reflexive. The subject is doing the action to themselves, getting themselves mixed up or entangled in a situation.

Could we use the inessive case (jossakin konfliktissa) if the conflict is already ongoing?