diff --git a/src/npc/newSlaveIncestSex.tw b/src/npc/newSlaveIncestSex.tw
index 30911592cb1932a7e03d57f92149160098afdd63..2f45ccad17bd41423788d7d76e35a55e9631270c 100644
--- a/src/npc/newSlaveIncestSex.tw
+++ b/src/npc/newSlaveIncestSex.tw
@@ -44,14 +44,14 @@
 		<<set _onelong = "younger "+_one >>
 		<<set _otherlong = "older "+_other >>
 	<<else>> /* twins, no real differentiation */
-		<<if $sissy.vagina == -1 && _one != "sister" && _one != "brother">>
+		<<if $sissy.vagina == -1 && _one != "brother">>
 			<<set _onelong = _one + " brother">>
-		<<else>>
+		<<elseif _one != "sister">>
 			<<set _onelong = _one + " sister">>
 		<</if>>
-		<<if $activeSlave.vagina == -1 && _one != "sister" && _one != "brother">>
+		<<if $activeSlave.vagina == -1 && _one != "brother">>
 			<<set _otherlong = _other + " brother" >>
-		<<else>>
+		<<elseif _one != "sister">>
 			<<set _otherlong = _other + " sister" >>
 		<</if>>
 	<</if>>