Yamabuki is a harmless young girl with a bright and positive outlook. However, she is likely to get out of control whenever she becomes engrossed with her newest idea or desires. She can't resist wanting to dress up cute girls and will cheerfully take their measurements.

She loves teasing others for the fun of it and sexually harasses the girls and insists that they let her do what she wants whenever the mood strikes her. Although it's unclear if she may actually be into both genders or if she only does it for her own amusement. However it is shown that she can get flustered if her targets get aggressive back at her, such as Myu grabbing her breasts when she grabbed hers, or when the Player pats her head when she sneaks into his room because he thought it was a dream.

It is confirmed that Yamabuki has an interest in anime and manga, hence her doujinshi career. She knows many different ones along with the exact details of many of them, allowing her to incorporate that into dates. 

Yamabuki is also pretty lazy. She is a procrastinator and waits till the last minute to write her doujinshi's before spending all nighters to work on them. This has led her to need the assistance of the player and the other club members on more than one occasion.

She is aware of the other girls and their crushes on the player, and sometimes uses that to tease them, much to the player's confusion.

(If you want you can add some of your own lines)