,vocaloid,kagamine len,kagamine rin,1boy,1girl,barefoot,blonde hair,blue eyes,blush,breasts,brother and sister,clothed sex,face-to-face,fingers to mouth,forehead-to-forehead,half-closed eyes,heads together,heavy breathing,hetero,implied sex,incest,interlocked fingers,lying,midriff,missionary,navel,nibbling,on back,open clothes,open mouth,ponytail,same (seirenmetal),school uniform,short ponytail,siblings,small breasts,socks,sweat,sweatdrop,twincest,twins,underboob