Talk:Marriage/@comment-162.217.51.175-20190307201753/@comment-38109392-20190408234418

The player must propose most of the time, though two NPCs can propose to the player: Gust and Mint.

Xu is unique in that he can ask the player to start dating, though he will not propose.

If I recall correctly, all three occurrences only happen after certain Romance missions, so it's not like they just come out of the blue.