Based on available sources, searches yield no concrete information about a character named "Yoshiko" within *Ningen Shikkaku: Director's Cut Ban*. Character sections for this title explicitly note details are incomplete or require contribution.

Synopses and descriptions solely focus on protagonist Youzou Ooba and his interactions with Tsuneko, omitting any reference to a Yoshiko character. User reviews and plot summaries similarly lack mention of this name.

References to other individuals named Yoshiko found during the search are unconnected to this film:
- Yoshiko Uchida (author)
- Yoshiko Tsushima (anime character from *Love Live! Sunshine!!*)
- Yoshiko Yamaguchi (historical figure)
- Yoshiko Kawashima (historical figure)
- Yoshiko M. Herrera (academic)

Therefore, no details regarding a character named Yoshiko specific to this anime can be confirmed.