Growing up is a thunderstorm. It’s not a steady hum that moves in lockstep with the second hand, but a nocturnal headrush of self-laceration, scatterbrained recollection and cognitive mapping, followed by a testing period. For some, that testing period gives way to a lifestyle change — they learn and mature. For others, the period lasts a day, and then it’s back to the drawing board. These are the tormented kids, perpetually adrift in smoke and attuned to everything’s fleeting nature. Chattanooga’s Isaiah Rashad is one of these kids, and his wonderful new album, “Cilvia Demo,” is a diaristic account of a young person’s shadowy self-actualizations in which he, or the narrator of the action, decides if becoming a man means growing up or giving up. Rashad is the latest artist unleashed by Los Angeles’ Top Dawg Entertainment. The label also houses mercurial gangster Schoolboy Q, druggy word nerd Ab-Soul, coarse-throated hardhead Jay Rock and rap’s current Prince Charming, Kendrick Lamar. Fervid fans often consider those four unparalleled talent in hip-hop’s new school. For the label to release Rashad onto this following with almost no established audience required a heap of good faith in the 22-year-old. In the digital age, rappers are typically scooped-up by a label with an independent fan base in tow. A debut record with this large a platform is a relic of the old A&R system. Yet TDE clearly sees promise in Rashad. “Cilvia Demo” is in line with the work of Rashad’s labelmates, necessitating patient and pensive listening. It’s a grower — its strokes are thin, and its thesis oblique. The music, muffled and meditative, recalls the warm alternative rap of the early 90s without the electricity. Pianos and muted keys ripple across the middle of the mix, ticking drum machines etch the downbeat and female vocalists whisper overhead. If this all sounds a bit sluggish, it can be — but it’s often luscious, a balmy bed of understated sounds for Rashad to brood over. And brood he does. Much like Lamar, Rashad is a tortured thinker, guarded and constantly at war with his conscience. He’s more interested in introspection than observation, though he sometimes intertwines the two artfully. On the title track, he looks in the eyes of a girlfriend’s son and sees himself as a toddler, glowering at his oft-absent dad. Like Eminem or Tyler, the Creator, he confronts his father’s absence with equal scorn and sadness. “And Daddy why you call me when you drunk? /And why you never call me when I need it / And I don’t wanna be like you no more / And I been trying to cope, I’m getting weak” he frets on “Heavenly Father.” He’s a nihilistic kid, so there’s much drug-talk — but it’s more in service of confession than glorification. The same can be said about the girl-talk. The lovely “West Savannah” is the only honest-to-God love song; otherwise, women are vices, the same as everything else. Rashad’s writing is charmingly naive and blessedly free of post-Jay-Z grandiosity, albeit short-sighted at certain points. It’s easy to picture him hunched over a notepad with a furrowed brow, pulling his frustrations out of the smoke and scribbling them down before they slip away. True to his generation, his songs are exasperated and disorganized. Catacomb thoughts, contemptuous exes, racist cops, fry cook workdays and scorched ashtrays all pop-up and vanish, visions in a lucid dream. In places, he hints more explicitly at a bleak past. One particular tangent, “And they don’t know my issues as a child / ’Cause I was busy cutting on myself / And hanging from the playground? ‘When in Rome’ / Until you got a rope around your neck,” helps erode the cynicism that tends to obstruct our empathy for angsty teens. Given the record’s overarching seriousness, it helps that Rashad is a gleefully adept rapper, capable of flicking words into one another like marbles on a Newton’s Cradle. He’s not overly technical, and save for underwhelming lyrical miracles like “Soliloquy” and “Modest,” he doesn’t let form get in the way of function. Sometimes, his hooks flop like tossed-off tweets (“N***** try to tell you what you want / but n***** rarely give you what you need” goes the particularly limp refrain on “Modest”), but mostly they stick, thanks to Rashad’s knack for four-bar dancehall ditties. His voice is leathery and rugged, and he’s got a great Tennessee drawl, stomping on consonant sounds and skating over vowels. “I’m scribing my living with curses / Just wait ‘til I get this s*** perfect,” Rashad seethes on “Banana.” “Cilvia Demo” is far from perfect, but watching an artist find his voice in real time is part of the appeal. The belief that “to be young is to be sad is to be high” will forever resonate with teens and 20-somethings. Rashad holds this belief dear, and though he’d stand to benefit from a broader point of view, he’s mastered the art of refusing to grow up or give up, depending on your perspective.