Page 17 confuses me. Her family name now is Nishi, but is her given name Touko or Sakurako? I've never heard of a Japanese person having more than one given name, half-Japanese with foreigner fathers can have two family names, but not the given name.
So she's either Touko Nishi ("Do It For Her" Ch.1) or Sakurako Nishi (this group Ch.1), which is it?
Also, I assume Toru was her previous family name before her mother remarried.
Edit: The note at the end clarifies this. Her name from now on should be Touko. Sakurako is non-canon and probably came from a misreading of the kanji.
Just to clarify, "子" (ko) is a kanji character, not hiragana. Hiragana (ko) is "こ".