Pretty self-explanatory, an adolescent that does not contribute to any aspect of life (others' lives or even their own) and waste otherwise productive hours with meaningless hobbies or tasks.
Not to be confused with gamers or otakus, as they actually put some effort into what they are doing. Teen sloths usually divulge themselves with texting, being emotionally distant, complaining about everything, or sleep at all hours of the day.
1.) Greg is such a teen sloth. I heard he slept for 18 hours straight because he spent the last 5 days texting until 3 am.
2.) Teen sloths give gamers and otakus a bad name because unlike online camaraderie and material/fictional admiration, teen sloths literally waste their lives doing nothing.