The Grasshopper(s) is a series of parody superheroes of the same name that each die shortly after they are introduced to spoof the tendency of superheroes dying and being replaced by a new hero with the same name. My main source was Wikipedia.
He was an employee for Roxxon Oil (an fictional oil company). He was a security guard that used a suit of power armor allowing him to jump superhuman heights, but provides little to no protection despite being armor. Doug has a crush on his co-worker Cindy Shelton, who has a crush on the Grasshopper (his alter ego). He tried to stop a robbery and joined the Great Lake Avengers... for five seconds, since the Batroc's Brigade (the people committing the robbery) killed him shortly after.
Neil was another Roxxon security guard that gained Doug's suit. However, it was altered and was more like Iron Man's. Cindy Shelton fell in love with him thinking he was the original Grasshopper. Unfortunately, she was Neil's cousin. So, Neil used his "Maximum Jump" to avoid her, which (according to Doorman) killed him because he exited the Earth's atmosphere and burned upon reentry into the Earth's atmosphere.
A person claiming to be "The All-New Grasshopper" was a member of the GLA (now called the "Great Lakes Initiative"). His neck was snapped by a disgruntled Deadpool when the latter was kicked off the team.
A fourth Grasshopper joined the team. He was revealed to be a Skrull (a type of shape shifting alien) impostor. Mr. Immortal (the team leader) was shocked while Big Bertha (a female member of the GLA) thought it was obvious.