This word is typically used in some parts of South America. According to the diccionary, it refers to someone who takes advantage of other people, especially the weakest. It can also mean 'annoying'. This word is quite easy to remember! 'Sangrón' comes from the word 'sangre' (blood), so you can think of someone who sucks other people's blood for his/her own benefit. Usually, of course, the 'victims' are weaker than him/her. Cheers.

thank you!

Antipático, odioso, pesado, insoportable etc

I'm spanish and I've never heard this before. I've heard "sangre" (blood) and "sangría" (a red typical Spanish drink). I hope I help you. ;)