Ok so there are a lot of people in this world that hate homosexual people. Personally, I think that homosexuals are some of the most funniest and kindest people ever. Some are even kinder than regular, straight people. And that's saying something. So when I say that I love Alec Lightwood, I am not exaggerating.
Alec is another character from Cassandra Clare's Mortal Instruments series. He is the parabatai of Jace Lightwood thus making him all the more likable. Some of what he does, he does out of arrogance and love for Jace. Yes I said it; Alec was in love with Jace though only becaue he refuse to fall for Magnus Bane. Sadly, jace wasnt quite aware of that though and that just made Alec all the more irritable. Irritable because he didn't want people to know that he was gay and so he did his best to hide it. Not the best option but that leads me into what I want to say about him.
For One, he is similar to Jace where their loved ones are concerned. Alec is the kind of person who would do just about anything for his family, especially his sister Isabelle and younger brother, Max. He doesn't always show it and he definitely doesn't like people knowing who he truly is but he is truly a heartfelt person regardless of his demeanor. He tends to be rather blunt to the point of cruelty and sarcasm but that's just him.
Another reason I find Alec Lightwood so likable is that he fights. Obviously he is a Shadowhunter and its required. But Alec is similar to Jace in his fervor towards fighting to protect his loved ones from demons and Downworlders: they both love to kick....butt. Alec is more of a protector than an actual offender but he still is a skilled fighter. Alec may not be as skilled as his parabatai, or as arrogant when it comes to fighting, but he can do some pretty amazing damage. Just look at what he did to his and Magnus's relationship in City of Lost Souls.
Long story short, he is a really cool guy who feels the need to impress everyone before himself. And that's just attractive in general aside from his blue eyes and black hair....