First encounder with younger sister

Beep Stories
It was a long time back when we were young. We were low middle class family and shared a single bedroom house in north Chennai. We were quite poor to afford dresses though by gods grace food was on table. This is weird but true as I My underwear used to go missing at times.
Much later I knew the true reason. One day morning after bath my underwear was missing. I was furious and was rummaging the draws. I asked if anyone knew it and all including my widowed mother and sister were quiet. I left for school without it.
I suspected that my sister was using it. I thought so because she had that wicked smile which I see on her usually during our sibling rivalry moments. So I hid behind the door and true enough she came in to change after school.
The moment she dropped her skirt and I saw it I jumped from behind and confronted her. She was furious and refused to give it to me. I was equally mad and told her that I will take it by myself. She dared me and I took the bait.
I lunged on her and tried to pull it down while she held it tightly. I tried pulling it down from the sides and my hand went to the front of the pussy and as the panty came down I withdrew my hand almost as a shock. the area was spongy, wet and red with blood. I ran away in panic.
After 30 minutes she came into the hall and I was very apologetic. She was quiet with anger. Mother sensed something was wrong. I realised how selfish I was and was determined to fix it. From the commission money I saved from buying family groceries,
I bought her a new set of underwear. I showed it to her and offered to put it on her as I made the mistake of pulling them down. She consented and stood before me with her skirt up. There was pubic hair I slid the panty up her thighs towards her hip.
It fit her smugly and that altered our relations. She thanked me and hug me tightly and we were in embrace for a long time. She offered to help me with my underwear and I stood naked before her. My dick was standing and as she was trying to fit my underwear was having fun in making
my dick stay inside the underwear. She pushed it but that only made it bigger. She held it for few minutes gently. We stood up and she removed her shirt. Her boobs were tiny but shapely. I held them in my mouth and suckled for a while.
After 2 to 3 years of intimate relationship we finally had sex the first time when I was 18. It continued till we got married. She lives with her children and family. When we meet we share our family concerns and remain best friends.