Party kara Tsuihou Sareta Sono Chiyushi, Jitsu wa Saikyou Nitsuki

A healer gets booted from his party because the leader notices he isn't really contributing much to the enough, the healer must look for new members to party with. After finding a cute martial artist to work together with, he reveals his secret - while he's a fairly mediocre healer, he actually fights well in close , here's the story of a support who's secretly a DPS, and where the entire conflict stems from the fact that he never told his old party he was DPS.