This is Milton, drawn in 3 stages of evolution.

Milton is the son of Milvus and Inella Scarlet. His two first evolutions resulted in different colors, fingers, and facial structures. He is a shy, self-doubting Inteleon who often flushes at the sound of praise, yet can get extremely mad when attacked with verbal nonsense.

While Milvus works with inflation science chemicals on himself, and Inella Scarlet is an Inteleon that works with water and air, Milton developed a mutation in which he generates air instead of water entirely. He also has an extremely shiny and stretchy hide and can puff up like a puffer fish. He often blimps without control when angry, shy, or blissful.

Milton developed two layers of skin. The inner layer holds everything together, while his outer hide resembles an inflatable suit. This outer layer is extremely stretchy, thick, and tough and can't be penetrated normally. This layer is connected to his air-generating Pokemon organ and windpipe, allowing him also to inhale air to inflate but, most importantly, vent the air out to deflate.

Milton can shoot some nasty high-pressure air bullets with these powers and generate air bombs. The problem is... he kinda is a lanky clumsy goofball.