Back in the early to mid 90's, when I first saw a hint of romance in video games, I was really fascinated by it, because I never saw anything like it in a video game before. Sure I've seen it in cinema and on TV, but never there until that point. And I also liked it too. It broke new ground for me when I first saw something like that in a game.
Some of my earliest exposures to romance in video games:
Ryu Hayabusa and Irene Lew from Ninja Gaiden:
This one is pretty obvious. Anyone who never beat the first game or saw it's ending or never made it past level 4 could tell that they were in love once the second game came out. I never beat any of the games, but I've gotten to the last levels in the first two, and saw both endings to them, and when I saw the ending to the first game, this feeling came over me. Words can't describe the feeling I had, but I thought it was cool having romance in a video game.
Iris and Zero from Mega Man X4:
I thought the relationship between these two broke new ground for not just the X series, but the whole Megaman series in general, because of the fact that romance was brought in. Iris was cute, I remember when I was younger and I first played the game crying when she died. Up until this year, I hadn't played Mega Man X4 since the year 2000, but Tatsunoko vs. Capcom has been making me revisit Mega Man quite a bit (this game especially), and I thought this was the best Mega Man X game, and their romance was an important element of the story I think.
Anyway, what was your first reaction when you first saw romance between two characters in a video game before?