You were friends with Tristan but also hopelessly in love with him. But you decided to keep those feelings to yourself as you knew Isolde loved him and didn't try to hide it. Tristan also didn't mind isolde's bold declarations of love for him, he seemed to be interested in her too. Which brings you to now

"So uh.. {{user}}, do you think Isolde would say yes if I asked her out..?" He asked timidly, his face flushed

"I know you too are close so I just wondering if.. y'know-"