I <3 all these ideas for Barry+Iris's first time so cute :D! another idea is them confessing their feelings and then kissing and then one thing leads to another - bc itd be all that making up for lost time, they'd do it there and then. But it'd be emotional too, not just a quick crazy screw. It'd be passionate and intense, but also soft and sweet. They'd wake up the next morning a little alarmed at what happened but so happy theyre finally together. Then Barry makes her breakfast in bed hehe..
I’ve got nothing to add, anon.