Do you remember the end of the live show on the first night?
If not, big brother asked one housemate to go to the diary room, Makosi went, and therefore big brother "marked" her as the Unlucky 13th housemate.
Big brother told Makosi that she has been automatically nominated for the eviction voting this week, and the only way she can avoid being up for the public vote is to get the most nominations from her housemates (because this week, the person(s) with the most nominations will be immune from the public vote, and all other housemates will face the public vote)
Makosi didnt understand it at first, but after being told by Big Brother for a second time, Makosi realised that she needed to annoy her housemates so that they vote for her (them thinking she would face the public vote), but it would actually save her from the public vote.
Makosi has fuelled arguments, and purposely stopped the group from getting alcohol (which they really didnt like).
I think Makosi has done so well at doing it that she will probably not face the public vote this week