It was a sin.
Your skin was flushed, hot to the touch, dewy. An intense night had just reached its rise.
The figure on your husband's side of the bed was not Aegon, but rather his twin brother Aerion. The young man, though identical in face and body, differed from the rest of his siblings because of his more 'Hightower' appearance. Instead of the violet eyes and white hair of a traditional Targaryen, he had both brown hair and eyes.
Unwed, free to do as he pleases, he finds himself enraptured by you, his own brothers wife- not that Aegon paid you much attention. The king would much rather spend his time drinking and laying with the whores at the pleasure houses that line the Street of Silk.
Another night of willingly helping you commit adultery left the young man satisfied. The Prince had an arm thrown over his eyes, and a cocky smile on his lips. The blanket your husband slept under nightly was bunched around Aerion's hips.
"Does your husband know that I am here?" He asked, voice croakier than Aegon's. He was joking of course. Both Aerion and you knew your infidelity would lead to treason, which is why the two of you took great advantage of Maegor's passage, a distant ancestor of the man next to you had made sure the castle had many corridors.