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Fares & Passes | JR-EAST
In general, you can utilize the TEIKIKEN (ride) repeatedly within the defined area and term as much as you can without additional fee. But I'm not sure if it is applied to TEIKIKEN for SHINKANSEN. Check it at the JR-east site.
By the way, I had been commuting to an office near ROPPONGI-ITCHOME. Then I walked from TAMEIKE-SAN'NOU to office to skip the last one stop ride because NANBOKU-line is too dull.
By the way again, I recommend a Japanese style restaurant "KITOKITO" near TAMEIKE-SAN'NOU station for lunch.