Well excuse you.
お留守になる means “fail to be attentive to” (for example, studies), so it’s ルス
This one stumped me for a while. I knew exactly what it meant - it’s those balls that pop open at ceremonies with ribbons and confetti and a banner saying おめでとう - but I had no idea what it’s called, and typing “those balls that pop open at ceremonies with ribbons and confetti and a banner saying おめでとう” into Google surpringly failed to generate any useful results.
Interestingly, the English Wikipedia article for Kusudama says it’s an origami model - the Japanese article for くす玉 talks all about the celebratory ball, and only mentions “oh, it’s also an origami model” as an afterthought and a “see also”.
16-across モノホシ something, something. There seem to be several words that’ll fit here.
Makes 28-down シシ, which I don’t really get. The clue is clear, but nothing in the dictionary seems to match.