Harass
Definition 1 of 3
Pro Tip 1/3
Continuous Action
Harass implies a persistent, ongoing annoyance, not just a one-time event. He harasses me with endless questions every day.
Pro Tip 2/3
Negative Connotation
Using 'harass' suggests an unwanted and negative experience. I felt harassed by the salesperson's aggressive tactics.
Pro Tip 3/3
Not Playful
Do not confuse teasing or joking with harassing, which is more serious. Teasing your friends is fine, but harassing them is not.