Worrying About Safety While Locked Up

Hi Everyone, As I mentioned in my intro post I am the male partner to Thrie. We are in a MMF bisexual triad, F is the more natural/inclined Dom but I have found some enjoyment out of the control aspects. Both of them say that I am a bratty Dom when I participate. He has done a fair amount of research and is usually a fairly conservative risk taker. She seems unconcerned about the safety, partially because she feels it is his risk to take and partially because of her belief that a cock can take some abuse/is already placed under pressure when erect. The two of them decided to purchase and use a ‘holy trainer 2’ a couple of weeks ago. After the initial couple day lock up I was surprised by how conflicted I was regarding it. I was initially bothered by the idea that, unlike other Dom/sub interactions, he couldn’t stop this at any time with a safe-word. I know that is the point but it still bothered me initially. It helped to remind myself that he can make the choice to stop the erotic game at anytime(not that he would want to) and either of us would immediately stop/unlock the device when we see him next. I enjoyed him being in the device but had anxiety regarding the safety - primarily with sleeping in the device and damaging his ability to get erections. The anxiety spiked when it was removed (no more erotic aspect of him being in the device to me) to the point that it effected my sleep that night, a very rare event for me. I also found I disliked the aesthetic of the device; it pulls his balls down and against the cock too much for my taste. I like a more natural look to some other devices. The anxiety was specifically that sexual teasing or activity in the device, that I was engaged in, was causing more attempts for his body to get hard and that those attempts cause damage.After the initial lock up I asked for a little time to do research into the safety before we started again. It seems that very little is available from medical research or considering the tissue/systems involved. The research I had done seems to reasonably conclude that a well fitting, occasionally worn device is of minimal risk. Based on this risk I decided to ‘exercise’ him out of the device daily and include that in the fun/game. It seems that it would decrease the risk and it adds to my enjoyment to use my control; so we locked him up for three days. I really enjoyed those three days with Thrie locked up but the exact same thing happened to me; the day after he was released I had horrible anxiety that effected my sleep. I found myself still focusing on times that I engaged in sex talk or teased him in the device. I am willing to accept that Thrie can choose something that causes damage (we drink alcohol afterall) but I can’t seem to get over direct activities I am doing that increase that damage. Based on this anxiety I went back to research - mainly to find out if the damage of wearing a chastity device comes from the body not have erections or from the pressure/force of trying to get them (and the devices do cause damage, otherwise you could wear them indefinitely with no negatives). Online there are stories online of men being locked up for months safely and stories of men with permanent damage from devices. Individual stories don’t seem to mean much. I also really dislike hearing stories of cock size decreasing or long term erection problems; I fully enjoy both topping and bottoming in sex with him and problems getting erections or decreases and size aren’t alright with me. The possibility of Peyronie’s disease also sounds horrible and it isn’t clear there are warning signs of reversible damage. So I am finding out a ton about the mechanics of erections and trying to figure out if I can answer the question that is causing me anxiety. If the damage is primarily caused by the lack of erections I can exercise him and figure out a rough length of time we are comfortable with. If the damage is primarily caused by the body attempting to get erect then it will ruin the fun I have with it. I don’t have any answers at this point but thanks for reading the long post.