GET /topic/%2523b%25E3%2583%25AA%25E3%2583%25BC%25E3%2582%25B0%25E3%2582%25AA%25E3%2583%25BC%25E3%2583%25AB%25E3%2582%25B9%25E3%2582%25BF%25E3%2583%25BC