She's the 39th wife to a man old enough to be her father. And she must take turns sharing the bed with him. Yet, she says she's madly in love and on top of the world.
When it comes to love, it's already hard fora man to split his attention between two women. Some would think Mr Ziona Chana, 67, is one lucky man. He has 39 wives who say they love him.
For Madam Siamthangi, being wife number 39 doesn't seem to matter, even if the love of her life is old enough to be her father.
"It's my privilege to be picked by Ziona to be his wife," she declares through an interpreter in a telephone interview from their home in Baktawng, a small village in Mizoram, in north-eastern India.
"Not every woman has a chance to marry the man she loves. I feel like I'm the luckiest woman in the world."
Madam Siamthangi, 30, who has a five-year-old daughter by Mr Chana, insists that there is no jealousy among the women.
"It's really not a big deal," she claims. "We each have our turns with Ziona. 'Big Sister' sees to it that the arrangement is a fair one."
"Big Sister" is Madam Zathiangi, 71, the first wife who runs the "Chhuanthar Run" (House of the New Generation), a four-storey mansion with 100 rooms and 17 bathrooms.
Madam Zathiangi, whom Mr Chana married when he was just 17, is clearly proud of her status - a point she admits in interviews with other media.
She says: "Being the eldest in the family, my job is to manage the household well.
"I've been married to Ziona the longest, so everyone in the family respects me."
Madam Zathiangi adds: "I take pride in looking after my husband, his needs and the family."
And taking care of Mr Chana's needs includes drawing up a roster for the younger wives - 22 of them are younger than 40 years old - to take turns to spend a week with him.
Spending a week with the man of the house means getting Mr Chana's undivided attention - which includes sharing his bed and having the chance to serve him, like prepare his bath and his clothes.
Wife number 34, Madam Rinkimi, 38, who married Mr Chana in 1999, says: "Serving him is like serving God. He's the most handsome man in this whole village, which is why I feel blessed to have him as my husband."
While Mr Chana sleeps in his own room with a double bed, his wives share rooms that resemble dormitories.
The rooms are sparsely furnished and each wife is allocated one bed and a cupboard.
The younger wives are assigned rooms nearer their husband's on the ground floor, while the older ones get rooms on the upper floor.
In an interview with Feminine, a magazine published in Malaysia, Mr Chana says: "It's just coincidence. When we first built this home, the wives were all put on the same level.
"Gradually, as I married more women, we ran out of space on that level and had to build partitions on the ground (floor)."
Not that the older wives mind.
Says Madam Zathiangi: "At our age - some of us are in our late 50s to 60s - it's okay even if Ziona does not share our beds."
Mr Chana is the head of a religious sect eponymously called Chana, founded in 1942 by his father. The sect allows polygamy.
He tells The New Paper on Sunday: "None of my wives was forced into marriage. They all fell in love with me because they know that I treat each of them with fairness and real love.
"It's not lust."
But there are reports suggesting that some of the women see the marriage as a ticket out of poverty.
It's inevitable, as he selects his wives from penniless peasant girls in the village, which is about four hours' drive away from Aizawl, the capital city of Mizoram state.
Most of the people there make a living from the timber and aluminium industries and agriculture.
Mr Chana does not dismiss the possibility that his wives are attracted to the "power" he "wields" in the village.
He says: "But there's nothing wrong with that as long as we are still very much in love."
Mr Chana's eldest son, Mr Parliana, 50, prefers to think of it as his father's good deeds.
He is quoted as saying: "Most of the women whom my father married were poor and orphan women in the village.
"By marrying them, he has set an example in the history of mankind. He has done so much for us."
His grandfather had seven wives.
Mr Parliana does not discount the possibility of his following his grandfather's or father's footsteps.
He is Mr Chana's only child who has two wives. They have 14 children between them.
He says: "If fate decrees so, then when the right woman comes along, I'll just have to marry her."
We asked Mr Chana how many children he has and he isn't too sure himself, which explains why there are conflicting numbers in the various news reports - from 86 children to as many as 94.
His married daughters do not live with him. but he is confident that he can remember all their names, including those of his children's spouses - 15 daughters-in-law and 26 sons-in-law - and his 50 grandchildren.
Says Mr Chana: "As the head of this big family, it's only natural that you make it a point to remember every name.
"Moreover, I am the one who named every child and grandchild."
While he insists he does not practise favouritism, Mr Chana confesses that he finds wife number 37, Madam Rohlupuii, 33, the prettiest.
He also believes that meeting Madam Siamthangi at the village entrance by chance one day was "a decree from God".
Says Mr Chana: "I didn't expect to fall in love again, but I couldn't help being attracted to her.
"There's no age or generation gap between us. She's so full of vibrancy that with her, I feel like I'm 10 to 20 years younger."
Madam Siamthangi is also confident that she is the last wife in Mr Chana's life.
Even if he has never indicated so, she says: "I don't believe he will marry again."
This article was first published in The New Paper.