I've got some nipple suckers. My experience has been that they do increase your nipple size, slightly. I think my nipples look pretty cool after taking them off after having them on thirty minutes! They're pretty swollen and really hard. Takes a while for them to get back to normal. I do think they've help increase the blood flow to my nipples though. 

My nipples are even my go-to place of sensation, when I can't do anything else. Like sitting at the couch at home (don't want to get stains, lol).

Like you, I was skeptical about nipple play. At first no real feelings there.  Others posts encouraged 'play' experiment, try lots of different ways to touch them.  I started to focus my nipple play when I was aroused, doing aless, or listening to 'ShibbySays Good Boy series' or reading arousing stories or this forum........

Now, a little lite nipple brush (even through my shirt) will start a little perineum glow or PC twitch.  mmmmm  and it grows from there.

Like penis size is an ego thing, nipple size is probably the same.  Mine are little, but very effective arousal triggers.

Sexagenarian here,  yes it is never too late to become prostate/nipple 'woke' 

Thanks to all who in the past have posted ideas,methods, and techniques about nipple play. My Aneros Adventure has been enhanced by your posts.

I will definitely do this a bit more.

Gotta admit, if you'd asked me about nipple play a few years ago, I'd have been a staunch sceptic. I've since found that playing with them for a few minutes gives some real nice sensations and even causes PC muscle involuntaries.

A year ago I was watching TV with my lady and she was playing with my nipple over my t-shirt, and out of the blue felt warm (all over? inside? in my head?) and out of breath. This nipple play is something every guy needs to experience. Only happened once.

While in lockdown, I will schedule some alone time to play - would it be best to use water based lubricant to stop the sore feeling?

Are those nipple sucker toys worth buying to increase sensitivity?

Old jogger's trick, Dax brand pomade on cotton pads. Stops chafing. Dax is a combo of vaseline, lanolin, and a bunch of other things that provide a lubricating buffer against irritation, while leaving everything soft. Preparation H does that too.

I don't know about increasing sensitivity, but you can definitely increase their size over time. Just google "nipple aspirators", nursing mothers use them for "shy nipples" so their infants have something to latch onto. 

Gotta admit, if you'd asked me about nipple play a few years ago, I'd have been a staunch sceptic. I've since found that playing with them for a few minutes gives some real nice sensations and even causes PC muscle involuntaries.

A year ago I was watching TV with my lady and she was playing with my nipple over my t-shirt, and out of the blue felt warm (all over? inside? in my head?) and out of breath. This nipple play is something every guy needs to experience. Only happened once.

While in lockdown, I will schedule some alone time to play - would it be best to use water based lubricant to stop the sore feeling?

Are those nipple sucker toys worth buying to increase sensitivity?

So if you ever thought you never had any sensitivity in one or the other or both, its basically "Use it or lose it". 

I'm starting to wonder if stimulating the prostate is similar to stimulating the nipples in the sense. Maybe practicing with the Aneros more will help, so long as I don't make myself sore?

I put down the Aneros sessions for some time, along with nipple stim so sensitivity in more ways than one mostly went away.

I regularly play with them again, though lately I think my nipples are a bit less tied to my penis, though they still can easily give me an erection a lot of the time. As far as trying to feel my prostate though, I feel as though nipple stim tends to take my attention into my chest rather than my pelvic region. It's still nice, just seems to override sensations down there at the moment.

On a slightly related note, I think I may be developing some sensitivity in my tongue...

I'm talking about increasing their responsiveness over time, not just what to do in a session. Exercising and training before the big game.