Tails!

After having pumped Sally full of your cum, your sperm begin to make their

way for the egg.

...

Your sperm reach the egg, and begin the process of fertilization. They succeed, and

Sally becomes pregnant with child. Although, she is unaware.

...

The next morning you are dead. Even though you have died, you did manage to

spread your seed before your demise. As such your legacy lives on, within

the womb of Sally.