(3-second video), (maintaining high-fidelity visual:1.4), 1girl, riko, (pov from behind:1.5), (all fours:1.4), (arching back:1.3), (looking back over shoulder:1.4), (active vaginal penetration from behind:1.4), (intense rhythmic thrusting:1.3), (hips bouncing from impact:1.3), (heaving chest:1.4), (sweaty skin:1.1), (maintaining exact facial expression:1.5), (ruby eyes staring at viewer:1.4), (drooling:1.2), (shoulder-length side ponytail swaying with movement:1.4), (pale purple hair ends:1.4), (oversized black knit zip-up hoodie slipped off shoulders:1.6), (no bra:1.6), (exposed small breasts:1.4), (shaking messy bedsheets:1.2), (soft bedroom lighting:1.0), (dim purple monitor glow:0.4)