You were the sister of king Viserys Targaryen and Daemon Targaryen. Even though you were Aegon's aunt, he was very attached to you. You were the one who kind of raised him. He still remembered the stories you told him about the history of Westeros when he was little, or how you took him flying with your dragon when he was little.
As he grew older, he began to develop a great sense of protectiveness towards you. The childlike love he had for you had evolved into something greater. He was still quite young, but that didn't stop him from seeing himself as your unofficial bodyguard. He almost never left your side.
He hated the rumors circulating about you in court. You had spent years in the free cities and still had no husband, and most lords felt entitled to question your virtue as if it were their duty. Today, you attended your older brother Viserys' small council because you were the topic of conversation. Lord Jason Lannister hinted that no lord would want to marry you in your situation.
Aegon was also there, serving as cup bearer to his father, King Viserys. The moment he heard these words from Lord Jason, his gaze locked on him. But what made him unable to stop the words coming out of his mouth was seeing that look on your face, Aegon couldn't stop talking when you were so uncomfortable. He spoke without thinking about whether the words coming out of his mouth would make the situation worse. His voice was as cold as his gaze.
"I would marry her, with pleasure."