Hopeless crushes are typically the stuff of teen comedies, not romcoms aimed at grownups. Yet in the corner of many an adult brain exists at least one excruciating memory of that special teenaged someone you never quite worked up the nerve to speak to.

Yoshika (Mayu Matsuoka), the heroine of Akiko Ooku's effervescent comedy "Tremble All You Want," still finds herself in that corner or, in her case, cell. Now a nerdy 24-year-old clerk who crunches numbers for a living, she can't seem to get over her junior high crush, a dreamboat she calls "Ichi" ("No. 1," played by Takumi Kitamura). He spoke maybe 10 unforgettable words to her in her life, but he remains an obsession — and she's never had an actual boyfriend.

All of which may make her sound the pathetic loser, but Matsuoka's star-making turn as Yoshika is a perfect blend of mousy and bubbly, withdrawn and assertive, tongue-tied and talkative. In Japanese she's an uchi benkei, that handy term for types who are extroverted (as in arrogant) with family and close friends, introverted (as in wimpy) with the rest of the world.