Shukumaru is Shuhei from the present, and he had been found and raised in the past all along, thus he is not her biological brother. Suzuko doesn't feel guilty about what happened to Shukumaru, however, when he tells her how much he's enjoyed his life in the past.
Shukumaru is Shuhei from the present, and he was found and raised in the past all along, so he is not her biological brother. Suzuko doesn't feel guilty about what happened to Shukumaru, however, when he tells her how much he enjoyed his life in the past.