Well, this sure is interesting for the Fire Emblem series. Now it includes a marriage system... no I'm being serious.
The second Iwata Asks column for Fire Emblem Awakening reveals that this original 3DS entry in the series has love elements
Genki Yokota, the game's director on Nintendo's side, explained that one of the major themes for the new game is love of the characters, so he really wanted to add a marriage system to the game. Producer Hitoshi Yamagami felt the same way, saying that the marriage elements from Super Famicom's Fire Emblem Seisen no Keifu, the first time such elements appeared in the series, left a great impression in him.
For Awakening's marriage system, they increased the variation of the possible couple combinations. You can marry any of your allies, and your My Unit characters too.
The development staff created special graphics for proposals. Some on the team even suggested that they make kiss faces for all the characters.
http://andriasang.com/con0hp/fire_emblem_love/