Ontas? is essentially like saying "Netflix and Chill" or "U up?"in Spanish. Ontas is a literal contraction of the question "¿Dónde estás?" (Where are you?), but in practical usage, it's a way of asking for sex.
According to Know Your Meme "ontas?" is currently trending because of a tweet from @DimeAlets where he DM'd Lily Collins (an English-American actress, and daughter of Phil Collins) on Instagram with the line "Ontas?" to which she responded, "What does 'ontas' mean?"
¿Ahora qué procede? pic.twitter.com/eiBP3W44wm— Alex Ruiz (@DimeAlets) April 16, 2019
Since then "ontas?" has erupted into people DMing celebrities and friends "ontas?" as well as "Ontas?" memes , which largely (so far) are self-deprecating and complaining that no one is sending them "ontas?".
Here are some examples of how "ontas?" is being used on Twitter:
Ontas? I prefer dick pics in my DMs.— Manila Luzon (@manilaluzon) April 19, 2019
me texting “ontas?” to all of my celebrity crushes pic.twitter.com/R0IhDC8tqi— ash ? (@ashleysguerrero) April 19, 2019
Wtf is Ontas? pic.twitter.com/quhKaMye6n— Xavier Serrano (@xserrano9) April 18, 2019
Everyone: Ontas— FredE (@FredyRalda) April 19, 2019
Jay Park told me Ontas? and I’m just like... pic.twitter.com/r9VW5Z4NQC— Nidia~ (@Fujoshi_666) April 19, 2019