He may be "true neutral," but doesn't he still have things he wants or desires? Or skills that might interest other people? Those could get someone interacting with him - with the former giving reason for him to approach other people (because he needs/wants something) or for other people to approach him (because they need/want something from him).
Or, in a general sense, discuss OOCly with the person you're trying to interact with to see why the two would do so. If the character themself is disinclined to engage, you kind of have to for them via OOC planning.
Or, in a general sense, discuss OOCly with the person you're trying to interact with to see why the two would do so. If the character themself is disinclined to engage, you kind of have to for them via OOC planning.
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