Happy Ha-Ha Bugs are bugs that tickle people. They appear in the episode Woozy Walden.
The species is first mentioned in the book that Wubbzy and Daizy were reading about the different bugs Walden was going to show.
Later in the episode, the bugs escape and start tickling Wubbzy, making him laugh hysterically and making him do things with his tail. They then attacked Daizy.
When Dr. Flooey arrived, the Happy Ha-Ha Bugs were still tickling the two, and were scattered across the floor. The bugs retreated after they heard him, but they still acted like they enjoyed their tickle fight.
Their final appearance was when Wubbzy asked if they forgot to put away the Happy Ha-Ha Bugs. While the crew did, they ended up tickling him again; this time, they also tickled Dr. Flooey and Widget. As they tickled Wubbzy and Daizy, they apppeared to attach themselves to their backs.
It is unknown what happened to the bugs afterwards, but they are likely still doing their tickle attacks to Wubbzy and Daizy.