. Shun lives with his mother and sister, Saemi. His father died several years ago.  After his father's death, Shun felt nothing but hate for him.  Mainly because his father, an engineer, was so consumed with finishing his experimental engine that he often wasn't able to keep his promises to Shun.  In one flashback, Shun told his dad that his toy plane was broken.  His father promised to fix it before that Sunday, when Shun was to play with it with his friends. Sunday came and Shun was the only one without a toy plane.  To further aggravate things, Shun kept hearing his father talking to his mom about the engine he was making.  Repeated instances like these made Shun think that his father wouldn't even make it to his graduation like he promised.  (Mrs. Ukiya was unable to attend as she was in the hospital.)  Sure enough, Shun's dad didn't make it as he was killed in a car accident.  Shun assumed his dad was testing his engine and was disheartened to realize that his father died without keeping a sing promise.  Shun refused to listen to his mother about this and also shrugged off anyone who mentioned his father (Mr. Matsuda:Ep 1, Ruriko:Ep 2).     Due to the death of his father, his family encounters financial problems now and then.  Shun even delivers newspapers before going to his old school everyday.  Thus, it was a great relief to his mother that Shun was offered a Kendo scholarship at Tategami Highschool--something his former teacher once suggested to him.  Shun feels a great responsibility for his sister, Saemi.  A part of this is taking his dad's place as the male figure at home and to be there for his sister.  Saemi and Shun, like almost all siblings, argue a lot but they share a great love for each other.     Saemi herself is growing up, feeling the pressure to be stronger as Shun isn't at home most of the time, and liking someone, Takeshi (Ep 20), who teased her a lot.  She thought more about Takeshi as he broke her hairclip (which Shun gave her years ago) and gave her a new one (by spending all of his allowance on it).  Saemi is also close friends with Yukino Houjo--the secret gatekeeper.     Later on near the final battle, Shun and the other gatekeepers discovered the original Gate Engine in his father's garage (Ep 23).  His mother told him that his father was determined to keep his promise to attend his graduation.  In his desperation to make it there on time, his gate power was awakened, but he was unable to control it, more so because it was amplified by the gate engine in his car.  His driving speed increased greatly which caused the accident that killed him.  Shun, upon realizing all this gained respect and love for his father, who became a part of his inspiration in the last battle.