Quicky handjob at family party for my stepbrother

Today was family day everyone was there, I haven't seen my uncle for a while ... it's probably been a couple of years now . I didn't even know that my stepbrother has become such a hottie haha ..I noticed all day long that we were both constantly looking for eye contact and flirting...Oh man I was already horny again anyway..so we just moved into the neighbour's room and I first jerked his cock properly and made him squirt hihi.

How would you have reacted?