A young girl whom Zoë Castillo meets at the cable car station outside the WATI Museum. Riko is waiting for her grandmother and little brother Hiro to come back from the museum. Her older brother Ren was supposed to be waiting with her, but Riko tells Zoë, sadly, that he met a girl while they were waiting, and he's left her on her own.
If Zoë helps out Kenji and Yuriko with their relationship woes, she can get an extra museum ticket and give it to Riko, who then boards the cable car with her. At the museum, Riko gets annoyed at Hiro calling her a crybaby, and retaliates by telling us more than we really needed to know about Hiro's own... issues. Her name-calling spurs him to prove he's not afraid by playing with the BunnyBot, so Zoë doesn't have to bribe Hiro with gum and everyone's happy.
Riko is voiced by Doireann Ní Chorragáin.