he / distal demonstrative, something far off removed from both speaker and listener: that / boyfriend

What? What did you say?

what / that thing (used in place of words you can't remember at the moment.)

Nothing

everything

sidelong glance, looking at someone sideways, looking out of the corner of one's eye

What?, Huh?

横目: sidelong glance, looking at someone sideways, looking out of the corner of one's eye

(adverbial particle, dismissive, derogatory) emphasizes disgust, contempt, or otherwise negative feelings of the speaker: whatever

dead, dried leaf