Mondo appears only in the CD drama "It's a White tomorrow! Team Rocket!"
Mondo is a young, eager Rocket member working for the Team Rocket Special Delivery Support Center(特別配達局員 Tokubetsu haitatsu kyoku'in). They provide support for Team members in the field, bringing them supplies, equipment, special items, even hand made lunch boxes! Mondo brings them new Meowth balloons and other machines. He looks up to his Sempai (先輩), or seniors, and aspires to be like them. Although, he's happy just to support them in their work. He has a crush on Jessie, and she uses this to make Mondo do what she wants.
Jessie convinces him to battle her, and beats him easily. They then offer to trade Mondo for his Ditto, saying that they'll be able to fight with it a lot and make it much stronger. In return they trade him Meowth against his will. Eventually though, Mondo says that what made him look up to the three Team Rocket members was the fantastic team that they made together. Meowth returns to the trio and Mondo gets his Ditto back.
When Jessie, James and Meowth depart in their Balloon, Jessie blows him a kiss, which thrills him. As they drift off he says:
Just like I thought, they're so COOL!
"Team Rocket's Top Secret File" has the following to say about Mondo:
Mondo is an apprentice member of Team Rocket's Special delivery Department who respects Jessie and James from the bottom of his heart. He brings them replacement Meowth Balloons, activity funds, and other tools for the sake of Team Rocket's glorious(?) operations.