I just have to feed my goldfish,"" or, ""I just have to finish this picture,"" Boris stalls at bedtime. ""The fact is,"" says his father, ""you just have to go to bed!"" Willoughby's depiction of little Boris' fear of monsters is snappy, and brushed with strokes of wry recognition; and Munsinger picks up her tone in Boris' expressions, and in the variously shaggy and lizard-like monster he imagines. The solution is conventional, but the perky touch is sustained: Boris' father buys him a watchdog to scare off the monsters--""He is little now, but he is growing very fast,"" Boris explains to his friends--but the dog proves to be afraid of the dark and Boris ends up protecting him. This breaks no new ground for monster picture books, but it goes through its paces without the ponderous crashings so common to the species.