At least Inigo is being kind enough here to not gloat his victory. He knows it sucks when you have to stay back because you've been hurt and have to recover, after all, so he actually feels a bit of sympathy for the guy. If anything, he's just glad Senku gave in so easily.

"I'll just keep an eye out for anything useful," he ends up saying. Because he's pretty sure Senku can't remember all the stuff he needs while his head is still not 100% back to normal.. "No worries, I'll be back soon enough. Don't go anywhere in the meantime, or I'll tattle on you!"

To who? Inigo doesn't even know, but he hopes the words are effective enough all the same.