Zettaizetsumei Dangerous Jii-san (2004)  

Grandpa Danger, 絶体絶命でんぢゃらすじーさん (2004), Zettai Zetsumei Dangerous Jiisan (2004)

The fictional character known as Grandpa Danger is renowned for his skills in falling off cliffs, dealing with a principal who has an inferiority complex, and escaping the dangers of sleep. Despite being nonsensical and disgusting, he is also relentless in his pranking behavior. His excessive phlegm and farts are so frustrating to Grandson that they cause him to laugh until his stomach splits.