Kaffeeklatsch solution
by Kegler
The eight entries that contain the string HEN squeeze those letters into a single square; 20 Across is HEN PARTY.
Across
| 1 | WALDO(RF)'S + A + LAD |  
| 9 | ACH(ENd)E |  
| 11 | I(LIA)'D (AIL rev) |  
| 13 | GEN(TL)E (LT rev) |  
| 14 | S(O-O)TY |  
| 15 | COMP + REH + END (HER rev) |  
| 17 | SA + TRAP (rev) |  
| 18 | GESTE (hidden) |  
| 20 | HEN PARTY |  
| 21 | R(I)OTS |  
| 23 | RA(U)NCH |  
| 26 | ENTHUSED (THE NUDES anag) |  
| 28 | D + OLES |  
| 29 | RUNST + O (TURNS anag) |  
| 30 | FAT + W + A |  
| 31 | T(H)ENET |  
| 32 | THEN + ETHER + L + AND + S |  
 
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Down
| 1 | WAG(E)S |  
| 2 | ACETAMINOPHEN (MENTION A CHEAP anag) |  
| 3 | DE(T)ER |  
| 4 | O + I(LCAN)S (NACL rev) |  
| 5 | FIR(M + WAR)E |  
| 6 | ADORE ("A DOOR" hom) |  
| 7 | AUTHENTICATED (AUNT CHEATED IT anag) |  
| 8 | DRY + DEN |  
| 10 | H + ENNA (rev) |  
| 12 | POE + S,Y |  
| 16 | O + PPO + SITE (POP anag) |  
| 18 | GR + A + DUAL (rev) |  
| 19 | CR(ED)IT |  
| 20 | HOTLY ("LOT HE" spoonerism) |  
| 22 | THE + F,T |  
| 24 | UINTA (hidden) |  
| 25 | sHOOTS |  
| 27 | A(SHE)N |  
 
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