[Ogawa Hidari] Playing in the mountains (COMIC LO 2011-04)

A bossy tomboy and her earnest childhood friend set out on a two-person 'exploration squad' trek through the mountain wilderness, only for their jungle adventure to derail when they unearth a discarded adult magazine among the trees. Curiosity spirals into fumbling hands-on discovery—her tight virgin pussy, his clumsy eager fingers, and a tearful defloration that leaves the stubborn girl wincing, blushing, and calling him a perv even as she lets him keep going. The real charm comes on the walk home, when she's sniffling on his back, berating him as an idiot, then quietly asking if they can do it all again sometime—provided he learns to be gentler.