Please, just consider.
I would say its an insult to RPG's if you tried to class it as one.
The Witcher series is a RPG, Dragon Age is a RPG and Romance Sim.
Mass Effect has no game play mechanics (That i can think off) that would classify it as a RPG.
At best i would say its a Romance Simulated 3rd person action (RPG).
And your narrowminding the romance part to just the end bit.
But its all about building relationships, that's all you do. You chat to Jacob, ask about his life, his past, his dad and help him find is dad and then he becomes loyal. 1 of the Bioware reps once mentioned that they were building a romance simulator and a girl was hired because of her romance novel writing ability.