A menstruating woman is permitted to comb the hair of a man in I'tikaf.

Sahih al-Bukhari · Book 33 · Hadith 2028

حَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، حَدَّثَنَا يَحْيَى، عَنْ هِشَامٍ، قَالَ أَخْبَرَنِي أَبِي، عَنْ عَائِشَةَ ـ رضى الله عنها ـ قَالَتْ كَانَ النَّبِيُّ صلى الله عليه وسلم يُصْغِي إِلَىَّ رَأْسَهُ وَهْوَ مُجَاوِرٌ فِي الْمَسْجِدِ، فَأُرَجِّلُهُ وَأَنَا حَائِضٌ‏.‏

Narrated `Aisha: The Prophet (ﷺ) used to (put) bend his head (out) to me while he was in I`tikaf in the mosque during my monthly periods and I would comb and oil his hair.