create_witch_effect

create_witch_effect = {
	#Gender
	random_list = {
		50 = { #Female
			modifier = {
				$WHO$ = { is_attracted_to_women = yes }
				add = 30
			}
			dummy_female = { save_temporary_scope_as = witch_gender }
		}
		50 = { #Male
			modifier = {
				$WHO$ = { is_attracted_to_men = yes }
				add = 30
			}
			dummy_male = { save_temporary_scope_as = witch_gender }
		}
	}

	#Create them
	create_character = {
		location = $WHO$.capital_province
		culture = $WHO$.culture
		faith = $WHO$.faith
		rite = $WHO$.rite
		gender = scope:witch_gender
		template = witchy_template
		random_traits = no

		after_creation = {
			give_witch_secret_or_trait_effect = yes

			#Sometimes adjust sexuality to create compatibility with WHO
			if = {
				limit = {
					$WHO$ = { is_attracted_to_gender_of = prev }
					NOT = { is_attracted_to_gender_of = $WHO$ }
				}
				random = {
					chance = 65
					set_sexuality = bisexual
				}
			}
		}
		
		save_scope_as = created_witch
	}
}

As written in game/common/scripted_effects/00_witch_effects.txt.