Derry is Princess Daisy's magical, talking parasol in Super Princess Daisy, who is used to attack members of the Koopa Troop on her way to rescue the Maria Bros. Throughout the game, Derry's past is revealed in the umbrella's dreams. It seems that he was originally a Human (or perhaps a Toad), and was turned into an umbrella by two strange figure's magic. He also appears as a trophy in Super Smash Bros.: The Ultimate All-Star Battle.
Once, Derry, not knowing who he was, got woken by a kindly old man, who then took him in. Eventually, Derry and his adopted "Grandfather" were interrupted by two figures, which are never shown but for their outlines. They announced that the boy had strange powers, and they must take him away. When the two refused, the figures turned Derry into an umbrella, but he was able to escape their grasp and was picked up by a merchant. He was eventually sold to Toadsworth, who gives Derry to Princess Daisy as she sets out after Bowser Jr. kidnaps Maria, Luise, and Toadette.
After Derry's last dream, he wakes up exclaiming that "Those two guys that kidnapped Grandpa are evil! Bowser Jr. is evil! Let's get 'im!" He then whispers to "Grandfather", telling him that he has decided to stay with the Princess for awhile, and that he wonders when they will be reunited.
Sadly, the ending of the game offers no further clues to his origin. He was not seen again, so it is unknown whether he is still an umbrella in Daisy's possession.
Derry has many forms that Daisy can use in her quest against Bowser Jr. Some of them can be obtained for free, but others must be purchased at the store. Derry's forms are:
- Bowlbrella - Derry acts as a boat to ferry Daisy across water.
- Chargebrella - This form allows Daisy to use Derry to destroy certain enemies and flip switches.
- Dashbrella - Daisy swings Derry around as she runs to defeat enemies in her path.
- Floatbrella - Using Derry, Daisy can float for a few seconds.
- Poundbrella - This form allows Daisy to Ground Pound enemies and breakable blocks in the ground.
- Slidebrella - This allows Daisy to slide down ropes with Derry.
- Subrella - Derry transforms into a sub so Daisy can use him to travel underwater.