Sid Davidson, known under the alias of Soggy Sid is a villain in Horry Henry, both in the books and the TV series.
He is Henry's PE coach. He is very mean, impatient, harsh and unattractive. He is also dance partners with Miss Battle-Axe, and they have a crush on each other. He is shown to be somewhat skinny, but has a large head.
In Horrid Henry Goes Swimming, he forces Henry to swim, although he has forgotten his swimming trunks. In Horrid Henry: Untouchable, he is seen dancing with Miss Battle-Axe. Later on, the class do running. By the time they finish, he deems it as "pathetic".