are you ready ... lol

if you smear one on white paper... is it really green ...

if so.. its poop ...; and you have to find the caterpillar ...

ken

ps: did anyone know that black licorice Dots are actually green ...

Looks like aphids to me. I'd blast them with the hose, a hard stream but not hard enough to knock the leaves off. Do that every couple/few days for a week or so, soon the ones you'll miss should be noticed and eaten by a "good" bug. Once you see those (likely ladybug larvae) at work, let them do their work.

Your ROS looks really close to the wall, but pics can be deceiving. Does the sun shine on it all day?

Black aphids are a known pest of ROS. Follow purple's advice about strong-ish sprays of water (and some hand squishing) . You'll have to do it every so soften, but you won't need to spray with chemicals.