Steve Rogers is a good friend, he’s a good teammate and a good soldier. So, he sits still in the plush leather seat, ignores the loud beat of the music, and watches his friend play. It’s Tony’s bachelor party. Tony gets to decide what he wants to do. 

Steve doesn’t crush his glass in his hand, because Steve is polite. Steve watches his friend be tied up and blindfolded by his fiance calmly. Steve doesn’t jump when a man feeds Tony his cock, or when Natasha orders him to ‘warm it’. Steve sits very quietly and watches Tony’s back as Natasha runs a finger over his spine. Steve is being supportive. Steve is being modern. Steve takes a calm sip of his unidentifiable cocktail and wishes he were a worse man.