This is the image he paints when describing how he feels about UMNO's behaviour, which he feels has worsened over the years.
He referred to a report about how former UMNO President and Prime Minister Tun Dr Mahathir Mohamad was told by an ex-senior UMNO leader that the party was rotten to the core (UMNO busuk hingga ke ususnya).
"Now, pus has oozed out (from the intestines or core). Pus-filled maggots have oozed out of UMNO," the Pan-Malaysian Islamic Party or Parti Islam Se-Malaysia (PAS) leader told Yahoo! Malaysia in an exclusive interview in Kota Bharu.
The 81-year-old leader said this when reacting to a question on the chances of success of the opposition alliance, Pakatan Rakyat (PR) or the People's Coalition against UMNO and its allies in the ruling Barisan Nasional coalition, in the upcoming 13th General Election.
"If democracy is allowed to run fairly, then we have a good chance." But Nik Aziz feels there are too many 'incidents' that have disrupted the fair running of Malaysia's democracy, and that 'unjust' policies have affected Kelantan.
The Kelantan Menteri Besar questions the need for all investment from the Federal Government to be channeled through Kelantan's Federal Development Department (or Jabatan Pembangunan Persekutuan Kelantan), and not be disbursed directly to the PAS-led state government but claims that there were no difficulties faced with private sector investments.
He claims that before 1990, investment from the Federal Government was given directly to the UMNO-held state government.
"Why have things changed? The investment is the Government's money, not UMNO's. And the Government is owned by the people."
Using the same tone, he questioned why Kelantan has not been awarded any oil royalties, an issue which even has the support of Tengku Razaleigh Hamzah, UMNO's Member of Parliament for Gua Musang.
The Federal Government must answer these questions, insists Nik Aziz.
"Democracy doesn't involve bribery, Islam says no to bribery, if they (UMNO) carry on with bribery, it is sinful."
Co-operation with Pakatan Rakyat
Nik Aziz says there is no reason for people to reject PR, and believes that being part of the alliance has strengthened PAS itself.
"In Kelantan, there is no reason why people should not accept PAS. There is development, there is no bribery (problems) and people move about freely."
He felt that there were no problems with PR, citing that PAS entered the pact with certain agreements, but did not explain the contents of these conditions.
"In the past, we accepted the invitation to join Barisan Nasional under (the late) Prime Minister Tun Abdul Razak's (administration).
"But when UMNO grew stronger, we were kicked out. So when we were asked to rejoin them, we did not. I said (to the them), 'I know you' ", indicating a clear rejection of UMNO's proposal.
"We rejected the invitation because UMNO was not loyal with agreements.
"We accept Pakatan Rakyat and until today, I have no problems with the coalition," he added, explaining that he also did not have any difficulties with opposition leader Datuk Seri Anwar Ibrahim.
But Nik Aziz was quick to brush off suggestions on whether Anwar could be a competent Prime Minister should PR take over Putrajaya, saying that these matters should be discussed "later".
Staying on, keeping strong leadership
Nik Aziz has no intention of stepping down, saying he will contest the upcoming polls because the party wants him to, only with one condition.
"The contest must be based on fair democratic practices, no phantom voters or devil voters, please."
Nik Aziz feels that it was not up to him to select a successor. "That has not crossed my mind, because that is not for me to choose." He explained that the best way was for the people to select a suitable candidate.
As PAS' spiritual leader for more than two decades, Nik Aziz beams when he is asked about his long leadership. "I am happy, happy with the support from party members and the wider community."
As to the party President's intention not to stand as candidate in the forthcoming polls, Nik Aziz says that if there is an opportunity for Datuk Seri (Hadi Awang) to strengthen and raise the image of the PAS, he should contest.
Fighting "sinful" phantom voters
Battling sin is mandatory and every Muslim's responsibility. Nik Aziz likens phantom voters to sins that must be fought, hence giving his support to April's Bersih 3.0 electoral reform rally.
He admits offering financial help to his supporters to attend the Kuala Lumpur demonstration, but does not feel that it has diluted Bersih's cause.
"As a Muslim, we have to go against these sins (phantom voters). If Pakatan Rakyat is elected to run the Federal Government, can UMNO accept us bringing in phantom voters? Of course not.
"So how are we (Pakatan Rakyat) going to accept that UMNO brings in phantom voters?"
Nik Aziz explained that seats won because of "phantom voters" were sinful and that demonstrations were allowed under the Federal Constitution. He also questioned the reason authorities blocked the sit-down demonstration.
"If they (ruling coalition) are afraid of criticism and opposition, run away-lah. Why rule Putrajaya?"