Logan Paul's gotta feel relieved after getting engaged to his boo, Nina Agdal ... which has gotta be why he took his fiancée on a boat after the big question for some R&R.
Logan and Nina were spotted soaking in the sun Monday, leaving the shoreside Grand Hotel Tremezzo on Lake Como -- and it didn't take long before he planted a kiss on his bride-to-be.
Of course, the WWE star popped his shirt off while on the water ... and Nina's view of her upcoming hubby is one we're sure she doesn't mind, either.
As we reported, sources close to the couple confirmed Logan proposed to Nina Sunday while on their Italian vacation.
He appeared in London for some wrestling just the day before, so the likely-sore guy is probably loving every minute of their vacay.
And that goes double for loving his future wife!!!