Does changing your name when you're dating have an effect on the entire town?

When I started dating Iroha, during the scene she says how she dreams of calling the person she is with by another name.

When I went to change the name I though she was referring to her name being changed but when it came up with my name I just reconfirmed it (in other words saying I want my name changed to my exact same name).

Now I am wondering: When Iroha (or any other girl if they do the same) asked if I wanted to be called something else, if I chose something more personal like "dear" or "honey" or even something not personal would the change only affect how she addressed me or also everyone else in town (ie. if i chose "Dear", Dunhil would start calling me "Dear" as well)?

Solution 1:

Only your lover calls you by the nickname entered during the blue heart event where you give your sweetheart a ring.