Scissors are Mikoto Urabe's weapon of choice.
Ayuko is very curious about Urabe's hobby, and wants to see it so badly that in episode 11 she snaps a naked photograph of Urabe to make Urabe angry enough to take out her scissors to destroy it (she had otherwise refused to demonstrate the skill).
In episode 12 it is revealed that she is trying to learn the skill herself, unfortunately by practicing it on her boyfriend Kouhei. In the progress of trying to give him a haircut, the scissors went flying out of her hand and stabbed him in the forehead.
This gave Kouhei an injury similar to the one which Akira received when Urabe accidentally stabbed him in the head with her scissors in the progress of cutting up his handkerchief, which she did because she was angry that he tried to hug her without asking permission first.
After injuring Kouhei, Ayuko did not give up her scissors habit, and actually had him hold gauze between his hands as she stabbed at it with scissors to try and cut it into a proper size for a bandage. This gave Kouhei lots of extra gauze clippings which he volunteererd to give Akira as a replacement for his which hadn't been changed.