If every male on earth got a boner at the same time, the earth's rotation would slow down. Assume there are about 3.8 billion males, with an average ♥♥♥♥ height of about 80 cm off the ground. The average ♥♥♥♥ weighs about 100 grams.
That's a combined mass of 380,000,000 kg of ♥♥♥♥.
Now we must make an approximation. For simplicity's sake, let us assume the penises are all evenly lined up in a ring around the equator. The equation for moment of inertia of a ring is I = mass*radius^2. The radius of earth is about 6.371 million meters. Therefore the radius of the approximated ♥♥♥♥ ring is 6,371,000 + 0.80 = 6,371,000.8 meters.
I = 380,000,000*6,371,000.8^2 = 1.5424*10^22
The Earth has a moment of inertia, I = 8.04×10^37 kg*m^2. The Earth rotates at a moderate angular velocity of 7.2921159 ×10^−5 radians/second. ​
Using Conservation of Angular Momentum we can find the new rotation of the earth.
L=I*omega= 8.04×10^37 kg*m^2 * 7.2921159 × 10^−5 = 5.86286*10^33. ​
5.86286*10^33 = (8.04×10^37 + 1.5424*10^22) *omega -> solve for omega = 7.292115899502489e-05 ​
This is 4.97511e-15 rad/s slower than earth's original rotation. This translates to 6.752*10^-10 seconds = 0.6752 nanoseconds longer per day. ​
If we all have a boner at the same time, we will collectively be able to last 0.6752 nanoseconds longer in bed. Stay hard fellas.