Bay Area dreamers WHY? have carved out an unusual niche over the past 15 years, marrying the verbal architecture of alternative rap with the introspection of indie rock. Playful but bittersweet, Moh Lhean picks up where 2012’s Mumps, Etc. left off, setting frontman Yoni Wolf’s meditations against music-box R&B (“Proactive Evolution”) and light, psychedelic folk (“The Barely Blur”). Nearly 40, Wolf is decidedly adult but retains the bruised optimism of a kid, like Peter Pan shouldering his way through real life.