Gay or straight?

https://en.m.wikipedia.org/wiki/Cameron_Monaghan

Read his 'Personal Life' section.
There's your answer :)

Why does it matter?

Hello? What a goofy question. He's an actor, and asking if he's gay is like asking Helen Mirren if she's really the queen of England or Keanu Reeves if he's really from another planet. Then again, that you'd even ask speaks to the integrity he brings to his character.

Oh my god, chill. OP is just curious, there is nothing wrong with that.

There is something wrong with it when this question has been asked over and over again...simply because he plays a gay character. His sexuality is no one's concern. And honestly it is immature and stupid to go around speculating on people's orientation. Also, the question was answered a long time ago. He said on twitter in 2013 that he is straight and that he found it strange that at this point in time he even needs to answer that question, that it shouldn't matter. He has had several girlfriends and never hid that.
So, yes it is wrong to ask this question. And people who go around doing this need to grow up and should be ashamed!

It's no different to asking any other question about a celeb.

Doctor Jagger, you need to grow up and stop attacking people on this board for asking a question. It sounds like it to me that you at one point wondered the same thing and took the time to find out about his interviews and find out how many girlfriends he's had. Again, you're the one that should grow up and stop being so...well you know. You're the type that goes around posting derogatory comments about people and their comments/questions when you're doing the exact same thing in a different manner. What an unbelievable moron you are. You're the problem sir and a simple answer would have been suffice. Instead you felt the need to talk about how inappropriate this question was. If we can't ask questions then what are these boards for. Doctor Jagger or doctor jerk of#???

exactly!