The Fashion Boy is Cool(1993)

お洒落小僧は花マルッ

When the bubbly 14-year-old Kotobuki falls in love with 26-year-old Hodaka, the owner and clothing designer of a popular boutique, she lies about her age in attempt to get closer to him. He is slow to warm up to her until a strange young man named Kazuomi asks Hodaka for part-time employment and stirs things up between them.