He first appeared in Captain Tsubasa ch. 51 "Opening Ceremony".

He's the private Language teacher of Tsubasa Ozora, who helped him during his last year of middle school in order to get prepared for his departure to Brazil. He usually appears in the Ozora household and also cheered his student in the finals of the middle school tournament.

Carlos is very cheerful but also determined to make Tsubasa a good learner, always teasing his student that he gives more importance to Football (even stopping lessons abruptly) than his Portuguese studies.