[Oshima Aki] Saikai (Toshiue Gentei) [SDTLs]

Yuuichi-kun and his beloved Natsuki Nee-chan reunite at the seaside after five years apart, where childhood admiration still lingers between the eager young swimmer and the busty older woman who once watched over him. Her playful praise for his form soon becomes a sultry invitation as she reveals her soft, heavy breasts and tempts him with an affectionate, hands-on lesson right on the sand. What begins as nostalgic teasing builds into a tender yet heated beachside affair where Natsuki takes the lead, guiding her flustered kouhai through his first intimate experience with aching sweetness and insatiable desire.