Something I noticed about sex

[Rumble]

I don't know whether it's me or does anyone feel it too. When I had sex with my wife, I noticed or should I say, I felt some sort of contraction from inside her vagina that lightly squeeze my penis a little bit. I didn't know vagina could do that. I only have sex with my wife, so I don't know if it just her or all women does that, heheee. Anyone else feels it too?