[Maka Fushigi] Kakuteru Sisters (Nekoja Nekoja 2) [YxTL]

A pushy big sister corners her little brother Hiroto, spray bottle in hand and zero patience for his protests that siblings can't do this, teasing him until he's pinning her against the bathroom toilet in a sweat-slicked frenzy. Her lust hits 'over-drive, 120 percent' as she takes him deep with a flushed, gasping grin, but the neglected label—'before using, please read the instructions carefully'—looms over a finale where the spray's true effects leave the whole family staring in shock. A comedic incest romp where the sister gets exactly what she wanted and the brother learns the hard way that mystery chemicals always come with consequences.