However, Liverpool had Simon Mignolet to thank for a first-half penalty save, while Mark Uth struck in the 87th minute to give the hosts a boost ahead of next Wednesday's second leg on Merseyside.
Klopp told BT Sport: "Hoffenheim had a specific plan to play. We gambled a little too much on the wing, it was a little dangerous in the first half, but as always when we play football, we found spaces in-between and created wonderful chances.
"The result is okay. The first half is done and if you said before the game we would win, I would take the result. We need Anfield, what an intense game for both sides. I am looking forward to a European night at Anfield. Only the person who does not know about Hoffenheim can be surprised by this."
The Reds remain unbeaten in their nine away Champions League qualifying matches, with seven wins and two draws.