Shizune is gifted with special eyes can sometimes see future events, a fact that she usually keeps a secret in order to avoid being mistreated by those who would doubt of her ability. Due to her power she carries complex feelings, for example she is bad at studying, but with her power obtaining the first place in every school exam is easy as the image of the answers will automatically come to her. She also feels guilty since whenever she reads the future of a person that equates to read a part of that person's life without permission. But, her biggest complex is her belief that whenever she foresees a disaster, she can't mend it at all; she strongly believes as the future that she sees as absolute and unchangeable, and thus sees herself as someone "cursed" to witness events without been able to do anything about it.
Shizune becomes an acquaintance of Mikiya Kokutou before she becomes roommates with Azaka and before Shiki and Mikiya becomes involved with Kirie Fujou's case. Mikiya was the first person to change a future predicted by Shizune as she predicted the death of a collar worker and Mikiya managed to pull him out from the danger at the last minute. Due to this Shizune sought friendship with Mikiya and disclosed her ability and circumstances to him; Mikiya on his part gives her warm advice about how she should change the way she sees herself and how she handles herself, thanks to this Shizune develops a slight attraction to Mikiya.
However, the moment she sees Shiki Ryougi Shizune understands, not only with her powers; but herself as a woman understands that she can't "surpass" Shiki's strong presence and gain a side next to Mikiya's heart. After a short interaction with Shiki, Shizune predicts that she will be the cause of Mikiya's death and decides to warn him (with no ill intention) that he should evade Shiki if he desires to live a long life. Mikiya tells her to stop her comments there; not because he thought that it was something insulting to Shiki, but because he didn't want to erase the possibility that he had to fulfill an important fate in his future. Mikiya understood perfectly that if he was going to push himself towards his own death, then he was doing so for Shiki's sake; and thus he decides to proceed forward to that fate without backing down. Seo could only watch how her "crush" walked bravely towards his future.
When Shizune actually meets Azaka for the first time and shakes hands with her, she actually predicts that they would become inseparable friends for all eternity and that they will have a marvelous time together. She thought that the fact that Azaka had the last name "Kokutou" was a coincidence.