His hand came up almost automatically to rest on her arm , a silent acknowledgement , and then gave a brief squeeze of affection . The cords of his hair were both springy and coarse against the sensitive tips of her breasts . His skin was cool from the morning air , but his inner furnace warmed her quickly . Resting her chin on his shoulder , she noticed the empty bay below . The night before had been dark , all color erased by the moonlight .

Based on the preceding passage, answer the following question Why are they outside without wearing any clothes ?
They had spent the night outside , making love under the moonlight .