I have already said she was cute, but I can't really talk about what was not revealed in cover art/basics. She has heterochroma!!! This is amazing, I love this unbalanced eye color, because every time I look her in the eyes at night, I am reminded of just how special she is to me.
Her battle attire also makes me go crazy. Her black shorts + thigh highs hit me with the same feeling as zettai ryoukai, that absolute zone that just becomes a target of absolute "joy." Beside that the rest of it is long, flowing, and just awesome, it is my favorite form of battle gear, which was admittedly first introduced to me by black rock shooter.
She is also very fast, strong, and overall would be able to overpower me... which I like for various reasons~
Now that I got what initially hooked me into liking Shizuru, I will now go into why I REALLY like her
Shizuru, cares for her friends and on many occasions will try and make sure their relationship will go well, even if she loves the same person. I HATE this, but I would HATE it if she was any other way, so I guess I love to hate this about her. I just want to go and push her forward so many times.
She doesn't mind it if people are perverts, and is understands that desire is a "healthy" thing. Being the pervert I am, I think she would be fairly accepting of all of this, and on due to similar occurrences, I believe she would be willing to play along with different types of sexual play, and be fairly willing to experiment.
Shizuru, has carried a lot on her tiny shoulders throughout her life. She has dealt with various feelings related to the incident with her family. Has seen many people die, and saved many others, and this really comes out in her character. She carries this, but it isn't easy for her. I really like this in her, and if nothing else wanting to help support her emotionally the best I can. This is just what happened throughout the game, I just wanted to hug her and burst into tears with her, just cry for hours, letting it all sort of flood out.