A sanguine technology mistress who owns a German BD-1 bicycle she nicknamed "Birdie." All she really wants is peace. She was formerly trained to be an idol, but Ranru hated it and left to work in the mechanical field. She is interested in anything mechanical, can create her own devices, and is a genius in mechanics. Ranru used to be afraid of nattō until she was forced to conquer it during a battle with a Trinoid. Ranru also carries a small camera with her and usually snaps photos of the enemy during mid-battle to come up with a strategy on how to defeat it. She sometimes has an itchy back and often wants others to scratch it for her. In the finale, Ranru goes to work at a racetrack. Her Burstosaur partner is Ptera.