While he's had plenty of girlfriends since sustaining the wounds while battling pro-Russian separatists in 2015, he has also had some dire experiences.

A woman he met via an app once walked away as soon as saw him.

Yet his rehabilitation process did not include any discussion of this topic, he said.

"The problem is we don't talk about sex at all."

More and more Ukrainian soldiers are facing the same challenge following Russia's full-scale invasion launched last year.

Breaking taboos about sex and how to enjoy it again after suffering war injuries is the aim of a project by a veterans' organisation in Kyiv, which Trystan took part in.

"It is a very taboo thing in Ukraine," said communication head Halyna Alomova, at VeteranHub, a drop-in centre for ex-servicemen in Kyiv.

The project, called "Resex", includes his-and-her manuals, a website and a video promotional campaign. It was funded by donors including Switzerland.

Researchers interviewed 29 veterans who suffered injuries in the war, aged 18 to 55, and 10 of their partners, using their anonymised responses.

"We concentrated on the physical impact (on sex). We asked people with amputations, with some very visible trauma," said Alomova.

"They had amputations, spinal injuries. They had some breakages. They had scars."

- 'Has to be light' -

Couples answered very differently to questions about sex, said project manager Bogdana Levytska, who carried out interviews, with some "very reserved".

"It all depends on how a person treated the issue of sex before the injury."

To kickstart a conversation, the team has put up posters on walls around Kyiv featuring stylised camouflage and questions and answers about sex.

"Can you still have a full sex life after injury?" one asks.

"Yes, you can have it all: a sex life and passion and tenderness and love. The main thing is love," one billboard responds.

Alomova said the project aims not just to help wounded soldiers, but also to change stereotypical views about Ukraine's armed forces.

In popular culture, they are shown as stern, austere figures who are "very powerful but very strict gods and they do not have a sex life", Alomova added.

The books "for him" and "for her" include frank talk about PTSD, sexual pleasure for both sexes and masturbation.

"After an injury, you can still arouse and get aroused... satisfy and be satisfied -- more than once," the video reassures.

The materials were designed to be "very easy and readable", said Alomova.

"There are so many materials written in medical or very 'NGO' language. But when we talk about sex, we have to be a bit fun. And it has to be light."

- 'Injuries too fresh' -

The creators acknowledged the project does not cover all kinds of couples or possible injuries.

No LGBTQ couple took part and the project creators were also only able to interview one injured servicewoman.

"The women with injuries we knew were not in the right emotional state to communicate, their injuries were too fresh," said Levytska.

She said the creators also struggled to get information on soldiers with genital wounds.

"Because there are almost no statistics at all. Usually, if a person receives a genital wound, he or she dies."

A physiologist and rehabilitation therapist told the project his military patients rarely ask about their sex life in consultations, she said.

But then it "somehow comes up in conversation".

The impact of amputations is less than that of internal injuries, which take a long time to heal and affect sensation, Levytska said.

- 'Prosthesis can fall off' -

Trystan, now 32, works on a helpline for VeteranHub, and agreed to appear in bed with a woman in a video promoting the project.

He said for him the main problems are not the mechanics of sex but meeting someone who is not put off by his injury.

"I'm functional in that I have legs, I have arms, I'm just having cosmetic problems and vision problems," he said.

"Maybe sometimes my prosthesis can fall off.

"Partners should accept my status," he added, estimating he has had around eight partners since his injury.

He prefers to meet dates in person, because he thinks his personality shines through better than on apps, but has received negative reactions.

"It is not very easy when you go on a date and the girl on this date just stands up and goes away."