This is a true experience that happened to me in my teens. I am a South Indian guy residing in Delhi. In our summer holidays we used to visit our relatives in our home town. My uncle's wife, my aunt was about 36-37 at that time though she looked much younger. From the time I became sexually conscious, she had been the object of my desire (though I felt guilty feeling that way about her). She was about 5' 3, slim, fair and incredibly sexy. I was about 19 then and my only sexual experience till then had been some innocent kisses with a neighbours daughter. That visit down south, my eyes kept straying over my aunts body when she was moving about. She once caught me looking down her cleavage when she was cleaning under the bed, but didn't say anything.
One day my parents, uncle and cousin had gone to attend a relatives marriage and were not expected to return till late evening. I had to go somewhere in the afternoon and so stayed at home with my aunt (though I didn't have anything funny in my mind). I was sitting on a sofa reading a novel when my aunt came and sat beside me. She was idly chatting with me while I was reading and her hand was resting on my thigh. I had reached a torrid section in my novel and got slowly aroused. My penis grew and then gently pushed against her hand from under my shorts. She did not remove her hand and suddenly I became very aroused. My heart was pounding and I started sweating when her hand covered my arousal and she gently squeezed it while continuing to talk to me of other things. You can be sure her I my mind was concentrating only on her hand. I kept my book down and looked at her to see a different look in her eyes. Her lovely bosom was moving up and down rapidly and she was breathing heavily. She suddenly got up and ran inside her bedroom.