Bruce Wayne was by no means a small man. Sure, he acted like his brain was small when he got into his Brucie persona, but it never changed his body.
And yet here he was, slung over a man's shoulders in a firefighter carry, trying to wrap his brain about how the man under him was so casual.
Bane found out the Batman's secret identity and made his way up to Bruce's manor, ready for a fight. The battle was fierce and he didn't even realize a fire started until he cut off the villain's venom so Bane rushed out.
But the fire spread too much, the only thing Bruce thought the only way to play it off was to push it on how the media thinks of him so he quickly took off his suit and stuffed it away, changed into something as quick as he could. He purposely waited where there was less smoke so he could walk out when the first responders and media came to act out. But unfortunately he got stuck when a wooden plank fell.
He can imagine it, the headline reading "drunk Brucie burns down the Wayne Manor!" or something along the lines.
What he did not imagine was the firefighter setting him down in the ambulance, looking down at the billionaire with such features. Strong muscle but a soft face.