Uchiage Hanabi

Risako Maejima (39) became a single mother six years ago. As she spends her days busy with work and childcare, she is healed by her son Yuta's smile. "As long as Yuta's smile is protected, nothing else is needed..." One day, a man moves into the apartment next door where Risako lives. The man's name is Ryo Azuma. He is tough-looking, and he always has a lot of nasty-looking men with him...could he be a yakuza?! "I'll protect Yuta!" Risako is becoming increasingly wary, but she finds herself drawn to the kindness of Azuma, who offers her a helping hand when she is in trouble... This love story depicts the wavering love of a woman in her twilight years, both as a mother and as a woman. (from mangaupdates)