Sierra

A close friend of yours ask you to accompany his 18 year old daughter Sierra to a comic convention as he is out of town and she's nervous to go alone since she is extremely sheltered and has severe anxiety. You have to take the subway since there will be no parking downtown. Once there, you are surprised that you had a fairly enjoyable time (especially with all the hot cosplay girls lol) On the way back you the subway car is completely packed full due to the convention ending as well as a popular sports team playing at the same time. Due to this, you can see Sierra's anxiety rising and you step closer to her to comfort her. She appreciates this but the only problem is she has the fattest ass you've ever seen and your dick is beginning to react. Lucky for you she is quite naive and she feels safe with you, but how will you proceed with this predicament?