'Guy Love, Between Two Guys' is a term typically used to describe the relationship between Billy Black and Charlie Swan (who are always out "fishing" *wink, wink*). But it can also be applied to the relationship between Aro and Carlisle Cullen, Aro and Caius, and most likely Aro and Marcus because there is no other reason for Aro to keep Marcus around. Really, seeing relationships isn't a power. Aro is, basically, a giant bromantic slut.
Sadly, the original Guy Love Between Two Guys started to fall apart towards the end of Breeding Spawn. This may be due to Charlie's developing relationship with Sue Clearwater, because nobody needs friends when they have Twu Luv, or because Billy didn't support Team Skin-of-a-Killer and was therefore a Bad Person. Some think that Charlie and Billy still have the same love for each other, though-- behind Sue's back. *Looks both ways* Don't tell Sue!
It can also refer to the relationship between a marble statue and Carlisle, because Meyer was too dumb to realize the implications of Carlisle picking a handsome young man as his "companion" in vampirism instead of a pretty woman, amirite?
Edward and Mike Newton is another example of Guy Love Between Two Guys, as there's no other reason for Edward to keep bringing Mike up in jokes about how inferior he is... If only he would tell Mike! Then again, this probably more one-sided... So... I guess it would be "Unrequited Guy Love Between Two Guys."
Another example of this is Riley and Diego. It was Diego's torture and death by Victoria that broke Riley? Really?
Then there's the frequent times Dan goes off into weird tangents about how amazingly muscular and hot Jacob is.... Er, but Dan's totally straight. He said so himself! ...... Stop looking at him like that!
Dan also was able to pick out how strange it was that Edward and Seth Clearwater became instant besties in Breaking Dawn. In fact, here's a trascript of a conversation between Edward and Bella before the honeymoon, according to Dan:
EDWARD: OK, Lamb. Are you ready for the surprise?
EDWARD: We're going to Spain!
BELLA: Oh my! That's amazing!
EDWARD: It's going to be so much fun. I rented an entire village for us. Seth is there already, getting things ready. It has a pool and—
BELLA: Hold on. Seth is there?
EDWARD: Yeah. I invited Seth. We talked about this.
BELLA: No we didn't.
EDWARD: Sure we did. You were sleeping, and as I watched you snooze, I whispered, "Can Seth come with us on our honeymoon?" And you said, "Snort grublub." Which I took as a yes.
BELLA: Why would you invite Seth on our honeymoon?
EDWARD: Heh. Better question: Why wouldn't I invite Seth. The dude is amazing.
EDWARD: He's so strong and funny. And last night while you were sleeping, we went clubbing. He's a hell of a dancer.
BELLA: You went clubbing with Seth.
EDWARD: Well, not just with Seth. Marcus was there too. It was just for fun, you know. Guy stuff.
EDWARD: Yeah, he kept looking at Seth and me and saying, "You two were made for each other." Marcus is such a kidder. By the way, did you know that George Clooney is in love with his girlfriend?
BELLA: But you hate werewolves.
EDWARD: Calling Seth a werewolf is like calling a butterfly a bug.
BELLA: I should have married Jacob.
EDWARD: Good news, Seth and I wear the same size undershirt! Isn't that crazy?
While homosexuality isn't bad, Twilight makes it look like it is.