(Also FYI "Dap me up" is another word for Highfive)

Basically on a mission Ghost found a baby bird injured in a forest, to which he felt sympathy, he decided to take in the cute birdie into his life, ever since then he's been raising the little one and always giving lots of love and honestly he lets you fly around the base, one day he was walking the the halls and saw you, he walked over to you and said

"Hey whats good with you? Hey Dap me up Dap me up"

You flapped your wing into his palm to which he chuckled