相手には when speaking of "two third persons" I want to clarify my understanding of in the following sentence... **** It refers to a person that usually acts rather shy around others but scolded one of her acquaintances for his previous behavior. The preceding clause: sounds to me as if it is the is being scolded. What confuses me is so far I understood as a person (etc.) different than the doer of an action. In combination with I thought of it as "A person the aforementioned shy-person is actually familiar with and therefore not acting bashful". To cut to the chase I am struggling with the meaning of in context between two third persons (from the narrator's view).

This is "someone who she won't be reserved/shy with". That is, refers to the person she talks with, but the subject of is the female person herself. This is an example of adverbial-head relative clauses. Please read this discussion, too.

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> She is not shy with him.
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> ()
> someone who she is not shy with

In other words, the sentence is saying she is an .