Golden Time Anime: How did Banri lose his memories?

Golden Time Anime has spent quite some time into the passage of time. Yet today we dare not from asking, how did Tada Banri lose his memories? Is his amnesia realistic?

Golden Time Review

Golden Time Anime: How did Banri lose his memories?

Golden Time Has Great Romance, Comedy And Drama -- And A Terrible

Banri Tada, Golden Time Wiki

Golden Time Episode 10

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Review for Golden Time Collection 2