Galko's skin got really dark as a result of tanning.
Otako comments that since Galko's skin has tanned so much, her nipples must be dark as well. Along with Ojou, Otako yells that Galko has dark nipples.
Mothers need to breastfeed their babies, 
but if you have inverted nipples,
على الأمهات إرضاع الأطفال من أثدائهن، لكن إن كانت حلماتكِ منقلبة
Mütter müssen ihre Babys stillen,
aber wenn du eingedrückte Nippel hast,
Los pezones invertidos afectan 
los conductos mamarios.
Une mère doit pouvoir
allaiter son enfant.
Perché una mamma deve allattare 
il proprio bambino,
Mães precisam amamentar os bebês,
 mas, com mamilos invertidos,