my sister's name is betty,

she's 57 now but at the time she was in her forties and me in my thirties.

she's 165 cm high,black hair,big breast and big butt.

at the time for convenience  i used to drive her to see my parents some sundays

that day i was driving her to her place(she was wearing a jean and a sweater)when she sadly asked me how i felt so happy being single cause she couldnt stand to be lonely. 

she started to cry.

i went out the road to park in an isolated area.

i put my harm around her shoulder to confort her. 

her:thx i needed it.

me:its ok feel better now?

her:hold me stronger please.

me:ok

her:starting a moaning sound.

me:dont do that

her what?

me:moaning feels strange

her:sorry but i like feeling you against me

me:dont say that it makes me hard

her:no answer

i was so excited that i kissed her with a passionate kiss .

she didnt push me so i said "suck your new boyfriend dick now" 

she smiled and unzipped my pants to give me a bowjob.

i started fingering her asshole.

i cummed so hard and she swallowed lots of it.

she was now smiling and i fucked her at her place.

she told me i could have fucked her many years ago if i just had asked her.

the only regret i got in my life is not fucking her sooner.

we fuck time to time but it's hard to keep our secret.

she let me do all i want to cause i'm her secret boyfriend