Eric, or "Buzz Bummerman" is a minor antagonist in 3 Ninjas: High Noon At Mega Mountain, and is only known as an acquaintence to Rocky.
Not much is known about Eric, other than he most likely goes to the same school as Rocky, considering he hangs out with Rocky's girlfriend, Jennifer and her two friends. Eric does seem to have one friend in the group, Doyle. But Doyle's rationality drives him to call out Eric every time he says or does something ridiculous.
Eric is known for being very cocky, and spends most of his time trying to steal Jennifer from Rocky, taking advantage of any situation that makes him look better than anyone else. Needless to say, he is very unsuccsessful.
3 Ninjas: High Noon At Mega Mountain
When we first meet Eric in 3 Ninjas: High Noon At Mega Mountain, he insults Colt and Tum-Tum for tagging along with Rocky's group of friends, desipite the whole trip being a celebration for Tum-Tum's birthday. Colt Responds to this by insulting Eric's obcene bleached-blonde fluffy haircut and calling him "Buzz" - a very hypocritical statement considering Colt himself is sporting a bizarre hairstyle that borrows elements of The Three Stooges' "Moe" mushroom cut and Steven Segal's iconic long length hair, resulting in an interesting ponytail/bowl cut hybrid.
Later on in the movie, we see Eric's numerous attempts at trying to make a fool out of Rocky (Puposefully bumping him and Jennifer at the bumper carts, pantsing Rocky in the bathroom, Beating him at a carnival game) but Rocky seems to just shrug it off. At one point, Eric begins making fun of Rocky for not wanting to go on a dangerous ride right after lunch by laughably flapping his arms and hopping up and down while making childish squawking and jeering chicken noises in some sort of new age court jester fashion. Rocky avoids this confrontation by offering to go search for his Jennifer's purse that she foolishly lost. When Eric continues to re-enact the infantile dance and yell at Rocky, Jennifer reponds by saying, "Shut up Eric, he's just being considerate." To which Eric says, "I'm considerate!" and he is interruped by his friend, Doyle, who shuts him up by saying, "Don't you mean conceited?" Eric slaps his friend at telling the truth.
In the final appearance of Eric, we see Rocky's group talking after riding a rollercoaser, Jennifer is complaining that Rocky has not shown up for a long time when she is interrupted by Carl, Zed, and Buelow : the 3 idiot nephews. Carl takes Jennifer away under the guise that he has a message from Rocky, not even considering the fact that Rocky never knew any guy that resembled Carl, and he could have easily been a criminal in disguise. Eric gets mad at them taking her away and shouts, "Hey Butthead! Maybe I'm her new boyfriend!" just to have Buelow scream in his face, causing Eric to urinate on himself. In his dejected state, Doyle further embarrasses him by pointing out his soiled jeans and announcing, "Bummerman, you peed your pants!" Giving Eric his second nickname, and he does not deny it.