Pepin rallied from a big deficit in the fifth game, but it wasn't enough as Alma pulled out a 25-13, 16-25, 25-15, 11-25, 15-9 road victory.
Senior middle hitter Janel Frank led the Lakers with six kills and three ace blocks. She also had two block assists. Kylee Haglund recorded three block assists.
Erika Johnson, a sophomore, added five kills and freshman Ali Murray finished with four ace serves. Pepin won 15 points on Murray's serve.
However, Alma had two skilled servers back-to-back in its rotation who delivered hard, deep serves that troubled the Lakers.
"We've done some switching around with our serve receive," Pepin coach Jamie Swiontek said. "We didn't feel 100 percent confident in the new things we were doing."
Pepin (5-5) plays host Tuesday to Elk Mound.