The militia navigators and gunners are two different groups (i.e. you cant hire the gunners as navigators, or viceversa). The 4 mercs can be hired as either gunners or navigators. Each character has a different personality (aggressive, serious or playful), so you can’t romance them in the same way (what works on one of them won’t work on the others, and their opinion of you changes also according to what you do, so an aggressive navigator will feel more attracted to you if you win fights, etc…) But, glad that some of you found this, and that it is also “hidden enough” that it does not detract from the game for those who are not interested in RO.
Also, Wilda can be romanced later on, though not sure anybody has done that? Also, is there an interest to make any other character romance-able?